Index: include/llvm/Analysis/OptimizationDiagnosticInfo.h
===================================================================
--- include/llvm/Analysis/OptimizationDiagnosticInfo.h
+++ include/llvm/Analysis/OptimizationDiagnosticInfo.h
@@ -132,6 +132,24 @@
                                    Inst->getParent(), Msg);
   }
 
+  /// \brief This variant allows specifying what should be emitted for missed
+  /// and analysis remarks in one call.
+  ///
+  /// \p PassName is the name of the pass emitting the message. If
+  /// -Rpass-missed= is given and \p PassName matches the regular expression, \p
+  /// MsgForMissedRemark is emitted.
+  ///
+  /// If -Rpass-analysis= is given and \p PassName matches the regular
+  /// expression, \p MsgForAnalysisRemark is emitted.
+  ///
+  /// The debug location and the code region is derived from \p Inst.
+  void emitOptimizationRemarkMissedAndAnalysis(
+      const char *PassName, Instruction *Inst, const Twine &MsgForMissedRemark,
+      const Twine &MsgForAnalysisRemark) {
+    emitOptimizationRemarkAnalysis(PassName, Inst, MsgForAnalysisRemark);
+    emitOptimizationRemarkMissed(PassName, Inst, MsgForMissedRemark);
+  }
+
   /// \brief Emit an optimization analysis remark related to floating-point
   /// non-commutativity.
   ///
Index: lib/Transforms/IPO/Inliner.cpp
===================================================================
--- lib/Transforms/IPO/Inliner.cpp
+++ lib/Transforms/IPO/Inliner.cpp
@@ -435,9 +435,10 @@
 
   for (CallGraphNode *Node : SCC) {
     Function *F = Node->getFunction();
-    if (!F)
+    if (!F || F->isDeclaration())
       continue;
 
+    OptimizationRemarkEmitter ORE(F);
     for (BasicBlock &BB : *F)
       for (Instruction &I : BB) {
         CallSite CS(cast<Value>(&I));
@@ -450,8 +451,15 @@
         // it.  If it is an indirect call, inlining may resolve it to be a
         // direct call, so we keep it.
         if (Function *Callee = CS.getCalledFunction())
-          if (Callee->isDeclaration())
+          if (Callee->isDeclaration()) {
+            ORE.emitOptimizationRemarkMissedAndAnalysis(
+                DEBUG_TYPE, &I,
+                Twine(Callee->getName()) + " will not be inlined into " +
+                    CS.getCaller()->getName(),
+                Twine("definition of ") + Callee->getName() +
+                    " is not available");
             continue;
+          }
 
         CallSites.push_back(std::make_pair(CS, -1));
       }
Index: test/Transforms/Inline/optimization-remarks.ll
===================================================================
--- test/Transforms/Inline/optimization-remarks.ll
+++ test/Transforms/Inline/optimization-remarks.ll
@@ -1,5 +1,7 @@
 ; RUN: opt < %s -inline -pass-remarks=inline -pass-remarks-missed=inline -pass-remarks-analysis=inline -S 2>&1 | FileCheck %s
 
+; CHECK: definition of fox is not available
+; CHECK: fox will not be inlined into bar
 ; CHECK: foo should always be inlined (cost=always)
 ; CHECK: foo inlined into bar
 ; CHECK: foz should never be inlined (cost=never)
@@ -32,6 +34,8 @@
   ret float %conv
 }
 
+declare i32 @fox()
+
 ; Function Attrs: nounwind uwtable
 define i32 @bar(i32 %j) #2 {
 entry:
@@ -48,7 +52,9 @@
   %call2 = call float @foz(i32 %sub1, i32 %3)
   %mul = fmul float %conv, %call2
   %conv3 = fptosi float %mul to i32
-  ret i32 %conv3
+  %call3 = call i32 @fox()
+  %add = add i32 %conv3, %call 
+  ret i32 %add
 }
 
 attributes #0 = { alwaysinline nounwind uwtable "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="false" }