Index: llvm/trunk/include/llvm/MC/MCWinCOFFStreamer.h
===================================================================
--- llvm/trunk/include/llvm/MC/MCWinCOFFStreamer.h
+++ llvm/trunk/include/llvm/MC/MCWinCOFFStreamer.h
@@ -73,7 +73,7 @@
   void EmitInstToData(const MCInst &Inst, const MCSubtargetInfo &STI) override;
 
 private:
-  LLVM_ATTRIBUTE_NORETURN void FatalError(const Twine &Msg) const;
+  void Error(const Twine &Msg) const;
 };
 }
 
Index: llvm/trunk/lib/MC/ELFObjectWriter.cpp
===================================================================
--- llvm/trunk/lib/MC/ELFObjectWriter.cpp
+++ llvm/trunk/lib/MC/ELFObjectWriter.cpp
@@ -630,28 +630,36 @@
     // In general, ELF has no relocations for -B. It can only represent (A + C)
     // or (A + C - R). If B = R + K and the relocation is not pcrel, we can
     // replace B to implement it: (A - R - K + C)
-    if (IsPCRel)
-      Asm.getContext().reportFatalError(
+    if (IsPCRel) {
+      Asm.getContext().reportError(
           Fixup.getLoc(),
           "No relocation available to represent this relative expression");
+      return;
+    }
 
     const auto &SymB = cast<MCSymbolELF>(RefB->getSymbol());
 
-    if (SymB.isUndefined())
-      Asm.getContext().reportFatalError(
+    if (SymB.isUndefined()) {
+      Asm.getContext().reportError(
           Fixup.getLoc(),
           Twine("symbol '") + SymB.getName() +
               "' can not be undefined in a subtraction expression");
+      return;
+    }
 
     assert(!SymB.isAbsolute() && "Should have been folded");
     const MCSection &SecB = SymB.getSection();
-    if (&SecB != &FixupSection)
-      Asm.getContext().reportFatalError(
+    if (&SecB != &FixupSection) {
+      Asm.getContext().reportError(
           Fixup.getLoc(), "Cannot represent a difference across sections");
+      return;
+    }
 
-    if (::isWeak(SymB))
-      Asm.getContext().reportFatalError(
+    if (::isWeak(SymB)) {
+      Asm.getContext().reportError(
           Fixup.getLoc(), "Cannot represent a subtraction with a weak symbol");
+      return;
+    }
 
     uint64_t SymBOffset = Layout.getSymbolOffset(SymB);
     uint64_t K = SymBOffset - FixupOffset;
@@ -784,8 +792,10 @@
                     Renames.count(&Symbol)))
       continue;
 
-    if (Symbol.isTemporary() && Symbol.isUndefined())
-      Ctx.reportFatalError(SMLoc(), "Undefined temporary");
+    if (Symbol.isTemporary() && Symbol.isUndefined()) {
+      Ctx.reportError(SMLoc(), "Undefined temporary symbol");
+      continue;
+    }
 
     ELFSymbolData MSD;
     MSD.Symbol = cast<MCSymbolELF>(&Symbol);
Index: llvm/trunk/lib/MC/MCAssembler.cpp
===================================================================
--- llvm/trunk/lib/MC/MCAssembler.cpp
+++ llvm/trunk/lib/MC/MCAssembler.cpp
@@ -179,14 +179,19 @@
 
   const MCExpr *Expr = Symbol.getVariableValue();
   MCValue Value;
-  if (!Expr->evaluateAsValue(Value, *this))
-    llvm_unreachable("Invalid Expression");
+  if (!Expr->evaluateAsValue(Value, *this)) {
+    Assembler.getContext().reportError(
+        SMLoc(), "expression could not be evaluated");
+    return nullptr;
+  }
 
   const MCSymbolRefExpr *RefB = Value.getSymB();
-  if (RefB)
-    Assembler.getContext().reportFatalError(
+  if (RefB) {
+    Assembler.getContext().reportError(
         SMLoc(), Twine("symbol '") + RefB->getSymbol().getName() +
                      "' could not be evaluated in a subtraction expression");
+    return nullptr;
+  }
 
   const MCSymbolRefExpr *A = Value.getSymA();
   if (!A)
@@ -196,9 +201,10 @@
   const MCAssembler &Asm = getAssembler();
   if (ASym.isCommon()) {
     // FIXME: we should probably add a SMLoc to MCExpr.
-    Asm.getContext().reportFatalError(SMLoc(),
-                                "Common symbol " + ASym.getName() +
-                                    " cannot be used in assignment expr");
+    Asm.getContext().reportError(SMLoc(),
+                                 "Common symbol '" + ASym.getName() +
+                                     "' cannot be used in assignment expr");
+    return nullptr;
   }
 
   return &ASym;
@@ -436,8 +442,13 @@
   // probably merge the two into a single callback that tries to evaluate a
   // fixup and records a relocation if one is needed.
   const MCExpr *Expr = Fixup.getValue();
-  if (!Expr->evaluateAsRelocatable(Target, &Layout, &Fixup))
-    getContext().reportFatalError(Fixup.getLoc(), "expected relocatable expression");
+  if (!Expr->evaluateAsRelocatable(Target, &Layout, &Fixup)) {
+    getContext().reportError(Fixup.getLoc(), "expected relocatable expression");
+    // Claim to have completely evaluated the fixup, to prevent any further
+    // processing from being done.
+    Value = 0;
+    return true;
+  }
 
   bool IsPCRel = Backend.getFixupKindInfo(
     Fixup.getKind()).Flags & MCFixupKindInfo::FKF_IsPCRel;
Index: llvm/trunk/lib/MC/WinCOFFObjectWriter.cpp
===================================================================
--- llvm/trunk/lib/MC/WinCOFFObjectWriter.cpp
+++ llvm/trunk/lib/MC/WinCOFFObjectWriter.cpp
@@ -706,14 +706,17 @@
 
   const MCSymbol &Symbol = Target.getSymA()->getSymbol();
   const MCSymbol &A = Symbol;
-  if (!A.isRegistered())
-    Asm.getContext().reportFatalError(Fixup.getLoc(),
+  if (!A.isRegistered()) {
+    Asm.getContext().reportError(Fixup.getLoc(),
                                       Twine("symbol '") + A.getName() +
                                           "' can not be undefined");
+    return;
+  }
   if (A.isTemporary() && A.isUndefined()) {
-    Asm.getContext().reportFatalError(Fixup.getLoc(),
+    Asm.getContext().reportError(Fixup.getLoc(),
                                       Twine("assembler label '") + A.getName() +
                                           "' can not be undefined");
+    return;
   }
 
   MCSection *Section = Fragment->getParent();
@@ -731,17 +734,21 @@
 
   if (SymB) {
     const MCSymbol *B = &SymB->getSymbol();
-    if (!B->getFragment())
-      Asm.getContext().reportFatalError(
+    if (!B->getFragment()) {
+      Asm.getContext().reportError(
           Fixup.getLoc(),
           Twine("symbol '") + B->getName() +
               "' can not be undefined in a subtraction expression");
+      return;
+    }
 
-    if (!A.getFragment())
-      Asm.getContext().reportFatalError(
+    if (!A.getFragment()) {
+      Asm.getContext().reportError(
           Fixup.getLoc(),
           Twine("symbol '") + Symbol.getName() +
               "' can not be undefined in a subtraction expression");
+      return;
+    }
 
     CrossSection = &Symbol.getSection() != &B->getSection();
 
Index: llvm/trunk/lib/MC/WinCOFFStreamer.cpp
===================================================================
--- llvm/trunk/lib/MC/WinCOFFStreamer.cpp
+++ llvm/trunk/lib/MC/WinCOFFStreamer.cpp
@@ -122,29 +122,37 @@
          "Got non-COFF section in the COFF backend!");
 
   if (CurSymbol)
-    FatalError("starting a new symbol definition without completing the "
-               "previous one");
+    Error("starting a new symbol definition without completing the "
+          "previous one");
   CurSymbol = Symbol;
 }
 
 void MCWinCOFFStreamer::EmitCOFFSymbolStorageClass(int StorageClass) {
-  if (!CurSymbol)
-    FatalError("storage class specified outside of symbol definition");
+  if (!CurSymbol) {
+    Error("storage class specified outside of symbol definition");
+    return;
+  }
 
-  if (StorageClass & ~COFF::SSC_Invalid)
-    FatalError("storage class value '" + Twine(StorageClass) +
+  if (StorageClass & ~COFF::SSC_Invalid) {
+    Error("storage class value '" + Twine(StorageClass) +
                "' out of range");
+    return;
+  }
 
   getAssembler().registerSymbol(*CurSymbol);
   cast<MCSymbolCOFF>(CurSymbol)->setClass((uint16_t)StorageClass);
 }
 
 void MCWinCOFFStreamer::EmitCOFFSymbolType(int Type) {
-  if (!CurSymbol)
-    FatalError("symbol type specified outside of a symbol definition");
+  if (!CurSymbol) {
+    Error("symbol type specified outside of a symbol definition");
+    return;
+  }
 
-  if (Type & ~0xffff)
-    FatalError("type value '" + Twine(Type) + "' out of range");
+  if (Type & ~0xffff) {
+    Error("type value '" + Twine(Type) + "' out of range");
+    return;
+  }
 
   getAssembler().registerSymbol(*CurSymbol);
   cast<MCSymbolCOFF>(CurSymbol)->setType((uint16_t)Type);
@@ -152,7 +160,7 @@
 
 void MCWinCOFFStreamer::EndCOFFSymbolDef() {
   if (!CurSymbol)
-    FatalError("ending symbol definition without starting one");
+    Error("ending symbol definition without starting one");
   CurSymbol = nullptr;
 }
 
@@ -281,9 +289,8 @@
   MCObjectStreamer::FinishImpl();
 }
 
-LLVM_ATTRIBUTE_NORETURN
-void MCWinCOFFStreamer::FatalError(const Twine &Msg) const {
-  getContext().reportFatalError(SMLoc(), Msg);
+void MCWinCOFFStreamer::Error(const Twine &Msg) const {
+  getContext().reportError(SMLoc(), Msg);
 }
 }
 
Index: llvm/trunk/lib/Target/AArch64/MCTargetDesc/AArch64MachObjectWriter.cpp
===================================================================
--- llvm/trunk/lib/Target/AArch64/MCTargetDesc/AArch64MachObjectWriter.cpp
+++ llvm/trunk/lib/Target/AArch64/MCTargetDesc/AArch64MachObjectWriter.cpp
@@ -90,9 +90,11 @@
     Log2Size = llvm::Log2_32(4);
     // This encompasses the relocation for the whole 21-bit value.
     switch (Sym->getKind()) {
-    default:
-      Asm.getContext().reportFatalError(Fixup.getLoc(),
-                                  "ADR/ADRP relocations must be GOT relative");
+    default: {
+      Asm.getContext().reportError(Fixup.getLoc(),
+                                   "ADR/ADRP relocations must be GOT relative");
+      return false;
+    }
     case MCSymbolRefExpr::VK_PAGE:
       RelocType = unsigned(MachO::ARM64_RELOC_PAGE21);
       return true;
@@ -170,25 +172,25 @@
   // assembler local symbols. If we got here, that's not what we have,
   // so complain loudly.
   if (Kind == AArch64::fixup_aarch64_pcrel_branch19) {
-    Asm.getContext().reportFatalError(Fixup.getLoc(),
-                                "conditional branch requires assembler-local"
-                                " label. '" +
-                                    Target.getSymA()->getSymbol().getName() +
-                                    "' is external.");
+    Asm.getContext().reportError(Fixup.getLoc(),
+                                 "conditional branch requires assembler-local"
+                                 " label. '" +
+                                     Target.getSymA()->getSymbol().getName() +
+                                     "' is external.");
     return;
   }
 
   // 14-bit branch relocations should only target internal labels, and so
   // should never get here.
   if (Kind == AArch64::fixup_aarch64_pcrel_branch14) {
-    Asm.getContext().reportFatalError(Fixup.getLoc(),
-                                "Invalid relocation on conditional branch!");
+    Asm.getContext().reportError(Fixup.getLoc(),
+                                 "Invalid relocation on conditional branch!");
     return;
   }
 
   if (!getAArch64FixupKindMachOInfo(Fixup, Type, Target.getSymA(), Log2Size,
-                                  Asm)) {
-    Asm.getContext().reportFatalError(Fixup.getLoc(), "unknown AArch64 fixup kind!");
+                                    Asm)) {
+    Asm.getContext().reportError(Fixup.getLoc(), "unknown AArch64 fixup kind!");
     return;
   }
 
@@ -200,8 +202,9 @@
     Type = MachO::ARM64_RELOC_UNSIGNED;
 
     if (IsPCRel) {
-      Asm.getContext().reportFatalError(Fixup.getLoc(),
-                                  "PC relative absolute relocation!");
+      Asm.getContext().reportError(Fixup.getLoc(),
+                                   "PC relative absolute relocation!");
+      return;
 
       // FIXME: x86_64 sets the type to a branch reloc here. Should we do
       // something similar?
@@ -229,16 +232,20 @@
       Writer->addRelocation(A_Base, Fragment->getParent(), MRE);
       return;
     } else if (Target.getSymA()->getKind() != MCSymbolRefExpr::VK_None ||
-               Target.getSymB()->getKind() != MCSymbolRefExpr::VK_None)
+               Target.getSymB()->getKind() != MCSymbolRefExpr::VK_None) {
       // Otherwise, neither symbol can be modified.
-      Asm.getContext().reportFatalError(Fixup.getLoc(),
-                                  "unsupported relocation of modified symbol");
+      Asm.getContext().reportError(Fixup.getLoc(),
+                                   "unsupported relocation of modified symbol");
+      return;
+    }
 
     // We don't support PCrel relocations of differences.
-    if (IsPCRel)
-      Asm.getContext().reportFatalError(Fixup.getLoc(),
-                                  "unsupported pc-relative relocation of "
-                                  "difference");
+    if (IsPCRel) {
+      Asm.getContext().reportError(Fixup.getLoc(),
+                                   "unsupported pc-relative relocation of "
+                                   "difference");
+      return;
+    }
 
     // AArch64 always uses external relocations. If there is no symbol to use as
     // a base address (a local symbol with no preceding non-local symbol),
@@ -246,20 +253,26 @@
     //
     // FIXME: We should probably just synthesize an external symbol and use
     // that.
-    if (!A_Base)
-      Asm.getContext().reportFatalError(
+    if (!A_Base) {
+      Asm.getContext().reportError(
           Fixup.getLoc(),
           "unsupported relocation of local symbol '" + A->getName() +
               "'. Must have non-local symbol earlier in section.");
-    if (!B_Base)
-      Asm.getContext().reportFatalError(
+      return;
+    }
+    if (!B_Base) {
+      Asm.getContext().reportError(
           Fixup.getLoc(),
           "unsupported relocation of local symbol '" + B->getName() +
               "'. Must have non-local symbol earlier in section.");
+      return;
+    }
 
-    if (A_Base == B_Base && A_Base)
-      Asm.getContext().reportFatalError(Fixup.getLoc(),
-                                  "unsupported relocation with identical base");
+    if (A_Base == B_Base && A_Base) {
+      Asm.getContext().reportError(
+          Fixup.getLoc(), "unsupported relocation with identical base");
+      return;
+    }
 
     Value += (!A->getFragment() ? 0 : Writer->getSymbolAddress(*A, Layout)) -
              (!A_Base || !A_Base->getFragment() ? 0 : Writer->getSymbolAddress(
@@ -309,10 +322,12 @@
       // we need to preserve and merge with the new Target? How about
       // the FixedValue?
       if (!Symbol->getVariableValue()->evaluateAsRelocatable(Target, &Layout,
-                                                             &Fixup))
-        Asm.getContext().reportFatalError(Fixup.getLoc(),
-                                    "unable to resolve variable '" +
-                                        Symbol->getName() + "'");
+                                                             &Fixup)) {
+        Asm.getContext().reportError(Fixup.getLoc(),
+                                     "unable to resolve variable '" +
+                                         Symbol->getName() + "'");
+        return;
+      }
       return recordRelocation(Writer, Asm, Layout, Fragment, Fixup, Target,
                               FixedValue);
     }
@@ -337,11 +352,13 @@
         Value +=
             Layout.getSymbolOffset(*Symbol) - Layout.getSymbolOffset(*Base);
     } else if (Symbol->isInSection()) {
-      if (!CanUseLocalRelocation)
-        Asm.getContext().reportFatalError(
+      if (!CanUseLocalRelocation) {
+        Asm.getContext().reportError(
             Fixup.getLoc(),
             "unsupported relocation of local symbol '" + Symbol->getName() +
                 "'. Must have non-local symbol earlier in section.");
+        return;
+      }
       // Adjust the relocation to be section-relative.
       // The index is the section ordinal (1-based).
       const MCSection &Sec = Symbol->getSection();
@@ -361,9 +378,10 @@
           return;
         }
       }
-      Asm.getContext().reportFatalError(Fixup.getLoc(),
+      Asm.getContext().reportError(Fixup.getLoc(),
                                   "unsupported relocation of variable '" +
                                       Symbol->getName() + "'");
+      return;
     }
   }
 
Index: llvm/trunk/lib/Target/ARM/MCTargetDesc/ARMAsmBackend.cpp
===================================================================
--- llvm/trunk/lib/Target/ARM/MCTargetDesc/ARMAsmBackend.cpp
+++ llvm/trunk/lib/Target/ARM/MCTargetDesc/ARMAsmBackend.cpp
@@ -395,8 +395,10 @@
       Value = -Value;
       isAdd = false;
     }
-    if (Ctx && Value >= 4096)
-      Ctx->reportFatalError(Fixup.getLoc(), "out of range pc-relative fixup value");
+    if (Ctx && Value >= 4096) {
+      Ctx->reportError(Fixup.getLoc(), "out of range pc-relative fixup value");
+      return 0;
+    }
     Value |= isAdd << 23;
 
     // Same addressing mode as fixup_arm_pcrel_10,
@@ -414,8 +416,10 @@
       Value = -Value;
       opc = 2; // 0b0010
     }
-    if (Ctx && ARM_AM::getSOImmVal(Value) == -1)
-      Ctx->reportFatalError(Fixup.getLoc(), "out of range pc-relative fixup value");
+    if (Ctx && ARM_AM::getSOImmVal(Value) == -1) {
+      Ctx->reportError(Fixup.getLoc(), "out of range pc-relative fixup value");
+      return 0;
+    }
     // Encode the immediate and shift the opcode into place.
     return ARM_AM::getSOImmVal(Value) | (opc << 21);
   }
@@ -544,8 +548,10 @@
     // could have an error on our hands.
     if (Ctx && !STI->getFeatureBits()[ARM::FeatureThumb2] && IsResolved) {
       const char *FixupDiagnostic = reasonForFixupRelaxation(Fixup, Value);
-      if (FixupDiagnostic)
-        Ctx->reportFatalError(Fixup.getLoc(), FixupDiagnostic);
+      if (FixupDiagnostic) {
+        Ctx->reportError(Fixup.getLoc(), FixupDiagnostic);
+        return 0;
+      }
     }
     // Offset by 4, and don't encode the low two bits.
     return ((Value - 4) >> 2) & 0xff;
@@ -559,16 +565,20 @@
     // Offset by 4 and don't encode the lower bit, which is always 0.
     if (Ctx && !STI->getFeatureBits()[ARM::FeatureThumb2]) {
       const char *FixupDiagnostic = reasonForFixupRelaxation(Fixup, Value);
-      if (FixupDiagnostic)
-        Ctx->reportFatalError(Fixup.getLoc(), FixupDiagnostic);
+      if (FixupDiagnostic) {
+        Ctx->reportError(Fixup.getLoc(), FixupDiagnostic);
+        return 0;
+      }
     }
     return ((Value - 4) >> 1) & 0x7ff;
   case ARM::fixup_arm_thumb_bcc:
     // Offset by 4 and don't encode the lower bit, which is always 0.
     if (Ctx && !STI->getFeatureBits()[ARM::FeatureThumb2]) {
       const char *FixupDiagnostic = reasonForFixupRelaxation(Fixup, Value);
-      if (FixupDiagnostic)
-        Ctx->reportFatalError(Fixup.getLoc(), FixupDiagnostic);
+      if (FixupDiagnostic) {
+        Ctx->reportError(Fixup.getLoc(), FixupDiagnostic);
+        return 0;
+      }
     }
     return ((Value - 4) >> 1) & 0xff;
   case ARM::fixup_arm_pcrel_10_unscaled: {
@@ -580,8 +590,10 @@
       isAdd = false;
     }
     // The value has the low 4 bits encoded in [3:0] and the high 4 in [11:8].
-    if (Ctx && Value >= 256)
-      Ctx->reportFatalError(Fixup.getLoc(), "out of range pc-relative fixup value");
+    if (Ctx && Value >= 256) {
+      Ctx->reportError(Fixup.getLoc(), "out of range pc-relative fixup value");
+      return 0;
+    }
     Value = (Value & 0xf) | ((Value & 0xf0) << 4);
     return Value | (isAdd << 23);
   }
@@ -599,8 +611,10 @@
     }
     // These values don't encode the low two bits since they're always zero.
     Value >>= 2;
-    if (Ctx && Value >= 256)
-      Ctx->reportFatalError(Fixup.getLoc(), "out of range pc-relative fixup value");
+    if (Ctx && Value >= 256) {
+      Ctx->reportError(Fixup.getLoc(), "out of range pc-relative fixup value");
+      return 0;
+    }
     Value |= isAdd << 23;
 
     // Same addressing mode as fixup_arm_pcrel_10, but with 16-bit halfwords
Index: llvm/trunk/lib/Target/ARM/MCTargetDesc/ARMELFStreamer.cpp
===================================================================
--- llvm/trunk/lib/Target/ARM/MCTargetDesc/ARMELFStreamer.cpp
+++ llvm/trunk/lib/Target/ARM/MCTargetDesc/ARMELFStreamer.cpp
@@ -509,8 +509,10 @@
   /// necessary.
   void EmitValueImpl(const MCExpr *Value, unsigned Size, SMLoc Loc) override {
     if (const MCSymbolRefExpr *SRE = dyn_cast_or_null<MCSymbolRefExpr>(Value))
-      if (SRE->getKind() == MCSymbolRefExpr::VK_ARM_SBREL && !(Size == 4))
-        getContext().reportFatalError(Loc, "relocated expression must be 32-bit");
+      if (SRE->getKind() == MCSymbolRefExpr::VK_ARM_SBREL && !(Size == 4)) {
+        getContext().reportError(Loc, "relocated expression must be 32-bit");
+        return;
+      }
 
     EmitDataMappingSymbol();
     MCELFStreamer::EmitValueImpl(Value, Size, Loc);
Index: llvm/trunk/lib/Target/ARM/MCTargetDesc/ARMMachObjectWriter.cpp
===================================================================
--- llvm/trunk/lib/Target/ARM/MCTargetDesc/ARMMachObjectWriter.cpp
+++ llvm/trunk/lib/Target/ARM/MCTargetDesc/ARMMachObjectWriter.cpp
@@ -150,10 +150,12 @@
   // See <reloc.h>.
   const MCSymbol *A = &Target.getSymA()->getSymbol();
 
-  if (!A->getFragment())
-    Asm.getContext().reportFatalError(Fixup.getLoc(),
+  if (!A->getFragment()) {
+    Asm.getContext().reportError(Fixup.getLoc(),
                        "symbol '" + A->getName() +
                        "' can not be undefined in a subtraction expression");
+    return;
+  }
 
   uint32_t Value = Writer->getSymbolAddress(*A, Layout);
   uint32_t Value2 = 0;
@@ -163,10 +165,12 @@
   if (const MCSymbolRefExpr *B = Target.getSymB()) {
     const MCSymbol *SB = &B->getSymbol();
 
-    if (!SB->getFragment())
-      Asm.getContext().reportFatalError(Fixup.getLoc(),
+    if (!SB->getFragment()) {
+      Asm.getContext().reportError(Fixup.getLoc(),
                          "symbol '" + B->getSymbol().getName() +
                          "' can not be undefined in a subtraction expression");
+      return;
+    }
 
     // Select the appropriate difference relocation type.
     Type = MachO::ARM_RELOC_HALF_SECTDIFF;
@@ -251,10 +255,12 @@
   // See <reloc.h>.
   const MCSymbol *A = &Target.getSymA()->getSymbol();
 
-  if (!A->getFragment())
-    Asm.getContext().reportFatalError(Fixup.getLoc(),
+  if (!A->getFragment()) {
+    Asm.getContext().reportError(Fixup.getLoc(),
                        "symbol '" + A->getName() +
                        "' can not be undefined in a subtraction expression");
+    return;
+  }
 
   uint32_t Value = Writer->getSymbolAddress(*A, Layout);
   uint64_t SecAddr = Writer->getSectionAddress(A->getFragment()->getParent());
@@ -265,10 +271,12 @@
     assert(Type == MachO::ARM_RELOC_VANILLA && "invalid reloc for 2 symbols");
     const MCSymbol *SB = &B->getSymbol();
 
-    if (!SB->getFragment())
-      Asm.getContext().reportFatalError(Fixup.getLoc(),
+    if (!SB->getFragment()) {
+      Asm.getContext().reportError(Fixup.getLoc(),
                          "symbol '" + B->getSymbol().getName() +
                          "' can not be undefined in a subtraction expression");
+      return;
+    }
 
     // Select the appropriate difference relocation type.
     Type = MachO::ARM_RELOC_SECTDIFF;
@@ -346,13 +354,15 @@
   unsigned IsPCRel = Writer->isFixupKindPCRel(Asm, Fixup.getKind());
   unsigned Log2Size;
   unsigned RelocType = MachO::ARM_RELOC_VANILLA;
-  if (!getARMFixupKindMachOInfo(Fixup.getKind(), RelocType, Log2Size))
+  if (!getARMFixupKindMachOInfo(Fixup.getKind(), RelocType, Log2Size)) {
     // If we failed to get fixup kind info, it's because there's no legal
     // relocation type for the fixup kind. This happens when it's a fixup that's
     // expected to always be resolvable at assembly time and not have any
     // relocations needed.
-    Asm.getContext().reportFatalError(Fixup.getLoc(),
-                                "unsupported relocation on symbol");
+    Asm.getContext().reportError(Fixup.getLoc(),
+                                 "unsupported relocation on symbol");
+    return;
+  }
 
   // If this is a difference or a defined symbol plus an offset, then we need a
   // scattered relocation entry.  Differences always require scattered
Index: llvm/trunk/lib/Target/Mips/MCTargetDesc/MipsAsmBackend.cpp
===================================================================
--- llvm/trunk/lib/Target/Mips/MCTargetDesc/MipsAsmBackend.cpp
+++ llvm/trunk/lib/Target/Mips/MCTargetDesc/MipsAsmBackend.cpp
@@ -63,15 +63,19 @@
     // address range. Forcing a signed division because Value can be negative.
     Value = (int64_t)Value / 4;
     // We now check if Value can be encoded as a 16-bit signed immediate.
-    if (!isInt<16>(Value) && Ctx)
-      Ctx->reportFatalError(Fixup.getLoc(), "out of range PC16 fixup");
+    if (!isInt<16>(Value) && Ctx) {
+      Ctx->reportError(Fixup.getLoc(), "out of range PC16 fixup");
+      return 0;
+    }
     break;
   case Mips::fixup_MIPS_PC19_S2:
     // Forcing a signed division because Value can be negative.
     Value = (int64_t)Value / 4;
     // We now check if Value can be encoded as a 19-bit signed immediate.
-    if (!isInt<19>(Value) && Ctx)
-      Ctx->reportFatalError(Fixup.getLoc(), "out of range PC19 fixup");
+    if (!isInt<19>(Value) && Ctx) {
+      Ctx->reportError(Fixup.getLoc(), "out of range PC19 fixup");
+      return 0;
+    }
     break;
   case Mips::fixup_Mips_26:
     // So far we are only using this type for jumps.
@@ -104,45 +108,57 @@
     // Forcing a signed division because Value can be negative.
     Value = (int64_t) Value / 2;
     // We now check if Value can be encoded as a 7-bit signed immediate.
-    if (!isInt<7>(Value) && Ctx)
-      Ctx->reportFatalError(Fixup.getLoc(), "out of range PC7 fixup");
+    if (!isInt<7>(Value) && Ctx) {
+      Ctx->reportError(Fixup.getLoc(), "out of range PC7 fixup");
+      return 0;
+    }
     break;
   case Mips::fixup_MICROMIPS_PC10_S1:
     Value -= 2;
     // Forcing a signed division because Value can be negative.
     Value = (int64_t) Value / 2;
     // We now check if Value can be encoded as a 10-bit signed immediate.
-    if (!isInt<10>(Value) && Ctx)
-      Ctx->reportFatalError(Fixup.getLoc(), "out of range PC10 fixup");
+    if (!isInt<10>(Value) && Ctx) {
+      Ctx->reportError(Fixup.getLoc(), "out of range PC10 fixup");
+      return 0;
+    }
     break;
   case Mips::fixup_MICROMIPS_PC16_S1:
     Value -= 4;
     // Forcing a signed division because Value can be negative.
     Value = (int64_t)Value / 2;
     // We now check if Value can be encoded as a 16-bit signed immediate.
-    if (!isInt<16>(Value) && Ctx)
-      Ctx->reportFatalError(Fixup.getLoc(), "out of range PC16 fixup");
+    if (!isInt<16>(Value) && Ctx) {
+      Ctx->reportError(Fixup.getLoc(), "out of range PC16 fixup");
+      return 0;
+    }
     break;
   case Mips::fixup_MIPS_PC18_S3:
     // Forcing a signed division because Value can be negative.
     Value = (int64_t)Value / 8;
     // We now check if Value can be encoded as a 18-bit signed immediate.
-    if (!isInt<18>(Value) && Ctx)
-      Ctx->reportFatalError(Fixup.getLoc(), "out of range PC18 fixup");
+    if (!isInt<18>(Value) && Ctx) {
+      Ctx->reportError(Fixup.getLoc(), "out of range PC18 fixup");
+      return 0;
+    }
     break;
   case Mips::fixup_MIPS_PC21_S2:
     // Forcing a signed division because Value can be negative.
     Value = (int64_t) Value / 4;
     // We now check if Value can be encoded as a 21-bit signed immediate.
-    if (!isInt<21>(Value) && Ctx)
-      Ctx->reportFatalError(Fixup.getLoc(), "out of range PC21 fixup");
+    if (!isInt<21>(Value) && Ctx) {
+      Ctx->reportError(Fixup.getLoc(), "out of range PC21 fixup");
+      return 0;
+    }
     break;
   case Mips::fixup_MIPS_PC26_S2:
     // Forcing a signed division because Value can be negative.
     Value = (int64_t) Value / 4;
     // We now check if Value can be encoded as a 26-bit signed immediate.
-    if (!isInt<26>(Value) && Ctx)
-      Ctx->reportFatalError(Fixup.getLoc(), "out of range PC26 fixup");
+    if (!isInt<26>(Value) && Ctx) {
+      Ctx->reportError(Fixup.getLoc(), "out of range PC26 fixup");
+      return 0;
+    }
     break;
   }
 
Index: llvm/trunk/lib/Target/PowerPC/MCTargetDesc/PPCMachObjectWriter.cpp
===================================================================
--- llvm/trunk/lib/Target/PowerPC/MCTargetDesc/PPCMachObjectWriter.cpp
+++ llvm/trunk/lib/Target/PowerPC/MCTargetDesc/PPCMachObjectWriter.cpp
@@ -241,12 +241,12 @@
     if (FixupOffset > 0xffffff) {
       char Buffer[32];
       format("0x%x", FixupOffset).print(Buffer, sizeof(Buffer));
-      Asm.getContext().reportFatalError(Fixup.getLoc(),
+      Asm.getContext().reportError(Fixup.getLoc(),
                                   Twine("Section too large, can't encode "
                                         "r_address (") +
                                       Buffer + ") into 24 bits of scattered "
                                                "relocation entry.");
-      llvm_unreachable("fatal error returned?!");
+      return false;
     }
 
     // Is this supposed to follow MCTarget/PPCAsmBackend.cpp:adjustFixupValue()?
Index: llvm/trunk/lib/Target/X86/MCTargetDesc/X86MachObjectWriter.cpp
===================================================================
--- llvm/trunk/lib/Target/X86/MCTargetDesc/X86MachObjectWriter.cpp
+++ llvm/trunk/lib/Target/X86/MCTargetDesc/X86MachObjectWriter.cpp
@@ -175,9 +175,10 @@
     // non-relocatable expression.
     if (A->isUndefined() || B->isUndefined()) {
       StringRef Name = A->isUndefined() ? A->getName() : B->getName();
-      Asm.getContext().reportFatalError(Fixup.getLoc(),
+      Asm.getContext().reportError(Fixup.getLoc(),
         "unsupported relocation with subtraction expression, symbol '" +
         Name + "' can not be undefined in a subtraction expression");
+      return;
     }
 
     Value += Writer->getSymbolAddress(*A, Layout) -
@@ -387,12 +388,12 @@
     if (FixupOffset > 0xffffff) {
       char Buffer[32];
       format("0x%x", FixupOffset).print(Buffer, sizeof(Buffer));
-      Asm.getContext().reportFatalError(Fixup.getLoc(),
+      Asm.getContext().reportError(Fixup.getLoc(),
                          Twine("Section too large, can't encode "
                                 "r_address (") + Buffer +
                          ") into 24 bits of scattered "
                          "relocation entry.");
-      llvm_unreachable("fatal error returned?!");
+      return false;
     }
 
     MachO::any_relocation_info MRE;
Index: llvm/trunk/test/MC/AArch64/error-location.s
===================================================================
--- llvm/trunk/test/MC/AArch64/error-location.s
+++ llvm/trunk/test/MC/AArch64/error-location.s
@@ -1,5 +1,49 @@
 // RUN: not llvm-mc -triple aarch64--none-eabi -filetype obj < %s -o /dev/null 2>&1 | FileCheck %s
 
+// Note: These errors are not always emitted in the order in which the relevant
+// source appears, this file is carefully ordered so that that is the case.
+
   .text
 // CHECK: :[[@LINE+1]]:{{[0-9]+}}: error: symbol 'undef' can not be undefined in a subtraction expression
   .word (0-undef)
+
+// CHECK: :[[@LINE+1]]:{{[0-9]+}}: error: expected relocatable expression
+  .word -undef
+
+// CHECK: :[[@LINE+1]]:{{[0-9]+}}: error: No relocation available to represent this relative expression
+  adr x0, #a-undef
+
+// CHECK: :[[@LINE+1]]:{{[0-9]+}}: error: Cannot represent a difference across sections
+  .word x_a - y_a
+
+// CHECK: :[[@LINE+1]]:{{[0-9]+}}: error: Cannot represent a subtraction with a weak symbol
+  .word a - w
+
+// CHECK: <unknown>:0: error: expression could not be evaluated
+  .set v1, -undef
+
+  .comm common, 4
+// CHECK: <unknown>:0: error: Common symbol 'common' cannot be used in assignment expr
+  .set v3, common
+
+// CHECK: <unknown>:0: error: Undefined temporary symbol
+  .word 5f
+
+// CHECK: <unknown>:0: error: symbol 'undef' could not be evaluated in a subtraction expression
+  .set v2, a-undef
+
+
+
+w:
+  .word 0
+  .weak w
+
+
+  .section sec_x
+x_a:
+  .word 0
+
+
+  .section sec_y
+y_a:
+  .word 0
Index: llvm/trunk/test/MC/ARM/arm-elf-relocation-diagnostics.s
===================================================================
--- llvm/trunk/test/MC/ARM/arm-elf-relocation-diagnostics.s
+++ llvm/trunk/test/MC/ARM/arm-elf-relocation-diagnostics.s
@@ -8,20 +8,19 @@
 @ CHECK: .byte target(sbrel)
 @ CHECK:       ^
 
-@ TODO: enable these negative test cases
-@ 	.hword target(sbrel)
-@ @ CHECK-SBREL-HWORD: error: relocated expression must be 32-bit
-@ @ CHECK-SBREL-HWORD: .hword target(sbrel)
-@ @ CHECK-SBREL-HWORD:        ^
-@
-@ 	.short target(sbrel)
-@ @ CHECK-SBREL-SHORT: error: relocated expression must be 32-bit
-@ @ CHECK-SBREL-SHORT: .short target(sbrel)
-@ @ CHECK-SBREL-SHORT:        ^
-@
-@ 	.quad target(sbrel)
-@ @ CHECK-SBREL-SHORT: error: relocated expression must be 32-bit
-@ @ CHECK-SBREL-SHORT: .quad target(sbrel)
-@ @ CHECK-SBREL-SHORT:        ^
+	.hword target(sbrel)
+@ CHECK: error: relocated expression must be 32-bit
+@ CHECK: .hword target(sbrel)
+@ CHECK:        ^
+
+	.short target(sbrel)
+@ CHECK: error: relocated expression must be 32-bit
+@ CHECK: .short target(sbrel)
+@ CHECK:        ^
+
+	.quad target(sbrel)
+@ CHECK: error: relocated expression must be 32-bit
+@ CHECK: .quad target(sbrel)
+@ CHECK:        ^
 
 
Index: llvm/trunk/test/MC/ARM/error-location.s
===================================================================
--- llvm/trunk/test/MC/ARM/error-location.s
+++ llvm/trunk/test/MC/ARM/error-location.s
@@ -1,5 +1,49 @@
 @ RUN: not llvm-mc -triple armv7a--none-eabi -filetype obj < %s -o /dev/null 2>&1 | FileCheck %s
 
+@ Note: These errors are not always emitted in the order in which the relevant
+@ source appears, this file is carefully ordered so that that is the case.
+
   .text
 @ CHECK: :[[@LINE+1]]:{{[0-9]+}}: error: symbol 'undef' can not be undefined in a subtraction expression
   .word (0-undef)
+
+@ CHECK: :[[@LINE+1]]:{{[0-9]+}}: error: expected relocatable expression
+  .word -undef
+
+@ CHECK: :[[@LINE+1]]:{{[0-9]+}}: error: No relocation available to represent this relative expression
+  adr r0, #a-undef
+
+@ CHECK: :[[@LINE+1]]:{{[0-9]+}}: error: Cannot represent a difference across sections
+  .word x_a - y_a
+
+@ CHECK: :[[@LINE+1]]:{{[0-9]+}}: error: Cannot represent a subtraction with a weak symbol
+  .word a - w
+
+@ CHECK: <unknown>:0: error: expression could not be evaluated
+  .set v1, -undef
+
+  .comm common, 4
+@ CHECK: <unknown>:0: error: Common symbol 'common' cannot be used in assignment expr
+  .set v3, common
+
+@ CHECK: <unknown>:0: error: Undefined temporary symbol
+  .word 5f
+
+@ CHECK: <unknown>:0: error: symbol 'undef' could not be evaluated in a subtraction expression
+  .set v2, a-undef
+
+
+
+w:
+  .word 0
+  .weak w
+
+
+  .section sec_x
+x_a:
+  .word 0
+
+
+  .section sec_y
+y_a:
+  .word 0
Index: llvm/trunk/test/MC/ARM/thumb1-relax-adr-local.s
===================================================================
--- llvm/trunk/test/MC/ARM/thumb1-relax-adr-local.s
+++ llvm/trunk/test/MC/ARM/thumb1-relax-adr-local.s
@@ -1,9 +0,0 @@
-@ RUN: not llvm-mc -triple thumbv6m-none-macho -filetype=obj -o /dev/null %s 2>&1 | FileCheck --check-prefix=CHECK-ERROR %s
-
-        .global func1
-        adr r0, Lmisaligned
-Lmisaligned:
-        .word 42
-
-@ CHECK-ERROR: misaligned pc-relative fixup value
-
Index: llvm/trunk/test/MC/ARM/thumb1-relax-bcc-local.s
===================================================================
--- llvm/trunk/test/MC/ARM/thumb1-relax-bcc-local.s
+++ llvm/trunk/test/MC/ARM/thumb1-relax-bcc-local.s
@@ -1,6 +0,0 @@
-@ RUN: not llvm-mc -triple thumbv6m-none-macho -filetype=obj -o /dev/null %s 2>&1 | FileCheck --check-prefix=CHECK-ERROR %s
-
-        bne Lfar
-        .space 258
-Lfar:
-@ CHECK-ERROR: out of range pc-relative fixup value
Index: llvm/trunk/test/MC/ARM/thumb1-relax-br-local.s
===================================================================
--- llvm/trunk/test/MC/ARM/thumb1-relax-br-local.s
+++ llvm/trunk/test/MC/ARM/thumb1-relax-br-local.s
@@ -1,8 +0,0 @@
-@ RUN: not llvm-mc -triple thumbv6m-none-macho -filetype=obj -o /dev/null %s 2>&1 | FileCheck --check-prefix=CHECK-ERROR %s
-
-        b Lfar
-        .space 2050
-
-Lfar:
-
-@ CHECK-ERROR: out of range pc-relative fixup value
Index: llvm/trunk/test/MC/ARM/thumb1-relax-ldrlit-local-behind.s
===================================================================
--- llvm/trunk/test/MC/ARM/thumb1-relax-ldrlit-local-behind.s
+++ llvm/trunk/test/MC/ARM/thumb1-relax-ldrlit-local-behind.s
@@ -1,7 +0,0 @@
-@ RUN: not llvm-mc -triple thumbv6m-none-macho -filetype=obj -o /dev/null %s 2>&1 | FileCheck --check-prefix=CHECK-ERROR %s
-
-Lhere:
-        ldr r0, Lhere
-
-@ CHECK-ERROR: out of range pc-relative fixup value
-
Index: llvm/trunk/test/MC/ARM/thumb1-relax-ldrlit-local-misaligned.s
===================================================================
--- llvm/trunk/test/MC/ARM/thumb1-relax-ldrlit-local-misaligned.s
+++ llvm/trunk/test/MC/ARM/thumb1-relax-ldrlit-local-misaligned.s
@@ -1,10 +0,0 @@
-@ RUN: not llvm-mc -triple thumbv6m-none-macho -filetype=obj -o /dev/null %s 2>&1 | FileCheck --check-prefix=CHECK-ERROR %s
-
-        .global func1
-_func1:
-        ldr r0, L_misaligned
-L_misaligned:
-        .word 42
-
-@ CHECK-ERROR: misaligned pc-relative fixup value
-
Index: llvm/trunk/test/MC/ARM/thumb1-relax-ldrlit-local-range.s
===================================================================
--- llvm/trunk/test/MC/ARM/thumb1-relax-ldrlit-local-range.s
+++ llvm/trunk/test/MC/ARM/thumb1-relax-ldrlit-local-range.s
@@ -1,13 +0,0 @@
-@ RUN: not llvm-mc -triple thumbv6m-none-macho -filetype=obj -o /dev/null %s 2>&1 | FileCheck --check-prefix=CHECK-ERROR %s
-
-        .global func1
-_func1:
-        ldr r0, L_far
-        .space 1024
-
-        .p2align 2
-L_far:
-        .word 42
-
-@ CHECK-ERROR: out of range pc-relative fixup value
-
Index: llvm/trunk/test/MC/ARM/thumb1-relax.s
===================================================================
--- llvm/trunk/test/MC/ARM/thumb1-relax.s
+++ llvm/trunk/test/MC/ARM/thumb1-relax.s
@@ -0,0 +1,35 @@
+@ RUN: not llvm-mc -triple thumbv6m-none-macho -filetype=obj -o /dev/null %s 2>&1 | FileCheck %s
+@ RUN: not llvm-mc -triple thumbv6m-none-eabi -filetype=obj -o /dev/null %s 2>&1 | FileCheck %s
+
+Lhere:
+@ CHECK: out of range pc-relative fixup value
+  ldr r0, Lhere
+
+@ CHECK: out of range pc-relative fixup value
+  b Lfar2
+
+@ CHECK: out of range pc-relative fixup value
+  bne Lfar1
+
+@ CHECK: out of range pc-relative fixup value
+  ldr r0, Lfar2
+
+@ CHECK: misaligned pc-relative fixup value
+  adr r0, Lmisaligned
+
+@ CHECK: misaligned pc-relative fixup value
+  ldr r0, Lmisaligned
+
+  .balign 4
+  .short 0
+Lmisaligned:
+  .word 42
+
+  .space 256
+Lfar1:
+  .word 42
+
+  .space 2050
+Lfar2:
+  .word 42
+
Index: llvm/trunk/test/MC/COFF/bad-expr.s
===================================================================
--- llvm/trunk/test/MC/COFF/bad-expr.s
+++ llvm/trunk/test/MC/COFF/bad-expr.s
@@ -1,7 +1,9 @@
 // RUN: not llvm-mc -filetype=obj -triple i386-pc-win32 %s 2>&1 | FileCheck %s
 
 // CHECK: symbol '__ImageBase' can not be undefined in a subtraction expression
+// CHECK: symbol '__ImageBase' can not be undefined in a subtraction expression
 
         .data
 _x:
         .long   _x-__ImageBase
+        .long   __ImageBase-_x
Index: llvm/trunk/test/MC/COFF/invalid-def.s
===================================================================
--- llvm/trunk/test/MC/COFF/invalid-def.s
+++ llvm/trunk/test/MC/COFF/invalid-def.s
@@ -1,5 +1,8 @@
-# RUN: not llvm-mc -triple i686-windows -filetype obj -o /dev/null %s
+# RUN: not llvm-mc -triple i686-windows -filetype obj -o /dev/null %s 2>&1 | FileCheck %s
 
+# CHECK: error: starting a new symbol definition without completing the previous one
+# CHECK: error: starting a new symbol definition without completing the previous one
 	.def first
 	.def second
+	.def third
 
Index: llvm/trunk/test/MC/COFF/invalid-endef.s
===================================================================
--- llvm/trunk/test/MC/COFF/invalid-endef.s
+++ llvm/trunk/test/MC/COFF/invalid-endef.s
@@ -1,4 +1,7 @@
-# RUN: not llvm-mc -triple i686-windows -filetype obj -o /dev/null %s
+# RUN: not llvm-mc -triple i686-windows -filetype obj -o /dev/null %s 2>&1 | FileCheck %s
 
+# CHECK: ending symbol definition without starting one
+# CHECK: ending symbol definition without starting one
+	.endef
 	.endef
 
Index: llvm/trunk/test/MC/COFF/invalid-scl-range.s
===================================================================
--- llvm/trunk/test/MC/COFF/invalid-scl-range.s
+++ llvm/trunk/test/MC/COFF/invalid-scl-range.s
@@ -1,6 +1,9 @@
 # RUN: not llvm-mc -triple i686-windows -filetype obj -o /dev/null %s
 
 	.def storage_class_range
+# CHECK: storage class value '1337' out of range
+# CHECK: storage class value '9001' out of range
 		.scl 1337
+		.scl 9001
 	.endef
 
Index: llvm/trunk/test/MC/COFF/invalid-scl.s
===================================================================
--- llvm/trunk/test/MC/COFF/invalid-scl.s
+++ llvm/trunk/test/MC/COFF/invalid-scl.s
@@ -1,4 +1,7 @@
-# RUN: not llvm-mc -triple i686-windows -filetype obj -o /dev/null %s
+# RUN: not llvm-mc -triple i686-windows -filetype obj -o /dev/null %s 2>&1 | FileCheck %s
 
+# CHECK: storage class specified outside of symbol definition
+# CHECK: storage class specified outside of symbol definition
+	.scl 1337
 	.scl 1337
 
Index: llvm/trunk/test/MC/COFF/invalid-type.s
===================================================================
--- llvm/trunk/test/MC/COFF/invalid-type.s
+++ llvm/trunk/test/MC/COFF/invalid-type.s
@@ -1,4 +1,7 @@
-# RUN: not llvm-mc -triple i686-windows -filetype obj -o /dev/null %s
+# RUN: not llvm-mc -triple i686-windows -filetype obj -o /dev/null %s 2>&1 | FileCheck %s
 
+# CHECK: symbol type specified outside of a symbol definition
+# CHECK: symbol type specified outside of a symbol definition
 	.type 65536
+	.type 65537
 
Index: llvm/trunk/test/MC/COFF/label-undefined.s
===================================================================
--- llvm/trunk/test/MC/COFF/label-undefined.s
+++ llvm/trunk/test/MC/COFF/label-undefined.s
@@ -1,4 +1,6 @@
 // RUN: not llvm-mc -filetype=obj -triple i386-pc-win32 %s 2>&1 | FileCheck %s
 // CHECK: assembler label 'Lundefined' can not be undefined
+// CHECK: assembler label 'Lundefined2' can not be undefined
         .text
         movl Lundefined, %eax
+        movl Lundefined2, %eax
Index: llvm/trunk/test/MC/COFF/secidx-diagnostic.s
===================================================================
--- llvm/trunk/test/MC/COFF/secidx-diagnostic.s
+++ llvm/trunk/test/MC/COFF/secidx-diagnostic.s
@@ -2,7 +2,9 @@
 // RUN: FileCheck %s < %t
 
 // CHECK: symbol 'bar' can not be undefined
+// CHECK: symbol 'baz' can not be undefined
 
 .data
 foo:
         .secidx bar
+        .secidx baz
Index: llvm/trunk/test/MC/ELF/common-error1.s
===================================================================
--- llvm/trunk/test/MC/ELF/common-error1.s
+++ llvm/trunk/test/MC/ELF/common-error1.s
@@ -3,4 +3,4 @@
         .comm   C,4,4
         .set    A,C
 
-// CHECK: Common symbol C cannot be used in assignment expr
+// CHECK: Common symbol 'C' cannot be used in assignment expr
Index: llvm/trunk/test/MC/ELF/common-error2.s
===================================================================
--- llvm/trunk/test/MC/ELF/common-error2.s
+++ llvm/trunk/test/MC/ELF/common-error2.s
@@ -3,4 +3,4 @@
         .set    A,C
         .comm   C,4,4
 
-// CHECK: Common symbol C cannot be used in assignment expr
+// CHECK: Common symbol 'C' cannot be used in assignment expr
Index: llvm/trunk/test/MC/MachO/AArch64/reloc-errors.s
===================================================================
--- llvm/trunk/test/MC/MachO/AArch64/reloc-errors.s
+++ llvm/trunk/test/MC/MachO/AArch64/reloc-errors.s
@@ -0,0 +1,10 @@
+; RUN: not llvm-mc -triple aarch64-none-macho %s -filetype=obj -o - 2>&1 | FileCheck %s
+
+; CHECK: error: conditional branch requires assembler-local label. 'external' is external.
+  b.eq external
+
+; CHECK: error: Invalid relocation on conditional branch
+  tbz w0, #4, external
+
+; CHECK: error: unknown AArch64 fixup kind!
+  adr x0, external
Index: llvm/trunk/test/MC/MachO/ARM/bad-darwin-ARM-reloc.s
===================================================================
--- llvm/trunk/test/MC/MachO/ARM/bad-darwin-ARM-reloc.s
+++ llvm/trunk/test/MC/MachO/ARM/bad-darwin-ARM-reloc.s
@@ -7,3 +7,9 @@
 L___fcommon: 
     .word 0
 @ CHECK-ERROR: unsupported relocation on symbol
+
+c:
+  .word a - b
+@ CHECK-ERROR: symbol 'a' can not be undefined in a subtraction expression
+  .word c - b
+@ CHECK-ERROR: symbol 'b' can not be undefined in a subtraction expression
Index: llvm/trunk/test/MC/MachO/bad-darwin-x86_64-diff-relocs.s
===================================================================
--- llvm/trunk/test/MC/MachO/bad-darwin-x86_64-diff-relocs.s
+++ llvm/trunk/test/MC/MachO/bad-darwin-x86_64-diff-relocs.s
@@ -2,4 +2,12 @@
 // RUN: FileCheck --check-prefix=CHECK-ERROR < %t.err %s
 
 .quad _foo - _bar
-// CHECK-ERROR: unsupported relocation with subtraction expression
+// CHECK-ERROR: error: unsupported relocation with subtraction expression
+
+_Y:
+.long (_Y+4)-_b
+// CHECK-ERROR: error: unsupported relocation with subtraction expression, symbol '_b' can not be undefined in a subtraction expression
+
+_Z:
+.long (_a+4)-_Z
+// CHECK-ERROR: error: unsupported relocation with subtraction expression, symbol '_a' can not be undefined in a subtraction expression
Index: llvm/trunk/test/MC/MachO/bad-darwin-x86_64-reloc-expr1.s
===================================================================
--- llvm/trunk/test/MC/MachO/bad-darwin-x86_64-reloc-expr1.s
+++ llvm/trunk/test/MC/MachO/bad-darwin-x86_64-reloc-expr1.s
@@ -1,6 +0,0 @@
-// RUN: not llvm-mc -triple x86_64-apple-darwin10 %s -filetype=obj -o - 2> %t.err > %t
-// RUN: FileCheck --check-prefix=CHECK-ERROR < %t.err %s
-
-_Z:
-.long (_Z+4)-_b
-// CHECK-ERROR: error: unsupported relocation with subtraction expression, symbol '_b' can not be undefined in a subtraction expression
Index: llvm/trunk/test/MC/MachO/bad-darwin-x86_64-reloc-expr2.s
===================================================================
--- llvm/trunk/test/MC/MachO/bad-darwin-x86_64-reloc-expr2.s
+++ llvm/trunk/test/MC/MachO/bad-darwin-x86_64-reloc-expr2.s
@@ -1,6 +0,0 @@
-// RUN: not llvm-mc -triple x86_64-apple-darwin10 %s -filetype=obj -o - 2> %t.err > %t
-// RUN: FileCheck --check-prefix=CHECK-ERROR < %t.err %s
-
-_Z:
-.long (_a+4)-_Z
-// CHECK-ERROR: error: unsupported relocation with subtraction expression, symbol '_a' can not be undefined in a subtraction expression
Index: llvm/trunk/test/MC/Mips/micromips-diagnostic-fixup.s
===================================================================
--- llvm/trunk/test/MC/Mips/micromips-diagnostic-fixup.s
+++ llvm/trunk/test/MC/Mips/micromips-diagnostic-fixup.s
@@ -1,9 +1,12 @@
 # RUN: not llvm-mc %s -triple=mipsel-unknown-linux -mcpu=mips32r2 -arch=mips -mattr=+micromips 2>&1 -filetype=obj | FileCheck %s
-#
+
+# Two instructions, to check that this is not a fatal error
+# CHECK: error: out of range PC16 fixup
 # CHECK: error: out of range PC16 fixup
 
 .text
   b foo
+  b foo
   .space 65536 - 6, 1   # -6 = size of b instr plus size of automatically inserted nop
   nop                   # This instr makes the branch too long to fit into a 17-bit offset
 foo:
Index: llvm/trunk/test/MC/Mips/micromips-pc16-fixup.s
===================================================================
--- llvm/trunk/test/MC/Mips/micromips-pc16-fixup.s
+++ llvm/trunk/test/MC/Mips/micromips-pc16-fixup.s
@@ -1,6 +1,6 @@
 # RUN: llvm-mc %s -triple=mips-unknown-linux -mcpu=mips32r2 -arch=mips -mattr=+micromips 2>&1 -filetype=obj | FileCheck %s
 #
-# CHECK-NOT: LLVM ERROR: out of range PC16 fixup
+# CHECK-NOT: error: out of range PC16 fixup
 
 .text
   b foo
Index: llvm/trunk/test/MC/Mips/mips-diagnostic-fixup.s
===================================================================
--- llvm/trunk/test/MC/Mips/mips-diagnostic-fixup.s
+++ llvm/trunk/test/MC/Mips/mips-diagnostic-fixup.s
@@ -1,9 +1,12 @@
 # RUN: not llvm-mc %s -triple=mipsel-unknown-linux -mcpu=mips32r2 -arch=mips 2>&1 -filetype=obj | FileCheck %s
-#
+
+# Two instructions, to check that this is not a fatal error
+# CHECK: error: out of range PC16 fixup
 # CHECK: error: out of range PC16 fixup
 
 .text
   b foo
+  b foo
   .space 131072 - 8, 1  # -8 = size of b instr plus size of automatically inserted nop
   nop                   # This instr makes the branch too long to fit into a 18-bit offset
 foo:
Index: llvm/trunk/test/MC/Mips/mips-pc16-fixup.s
===================================================================
--- llvm/trunk/test/MC/Mips/mips-pc16-fixup.s
+++ llvm/trunk/test/MC/Mips/mips-pc16-fixup.s
@@ -1,6 +1,6 @@
 # RUN: llvm-mc %s -triple=mips-unknown-linux -mcpu=mips32r2 -arch=mips 2>&1 -filetype=obj | FileCheck %s
 #
-# CHECK-NOT: LLVM ERROR: out of range PC16 fixup
+# CHECK-NOT: error: out of range PC16 fixup
 
 .text
   b foo