diff --git a/clang/lib/Driver/ToolChains/Clang.cpp b/clang/lib/Driver/ToolChains/Clang.cpp
--- a/clang/lib/Driver/ToolChains/Clang.cpp
+++ b/clang/lib/Driver/ToolChains/Clang.cpp
@@ -4675,8 +4675,8 @@
 
   // Enable -mconstructor-aliases except on darwin, where we have to work around
   // a linker bug (see <rdar://problem/7651567>), and CUDA device code, where
-  // aliases aren't supported.
-  if (!RawTriple.isOSDarwin() && !RawTriple.isNVPTX())
+  // aliases aren't supported. Similarly, aliases aren't yet supported for AIX.
+  if (!RawTriple.isOSDarwin() && !RawTriple.isNVPTX() && !RawTriple.isOSAIX())
     CmdArgs.push_back("-mconstructor-aliases");
 
   // Darwin's kernel doesn't support guard variables; just die if we
diff --git a/clang/test/Driver/aix-constructor-alias.c b/clang/test/Driver/aix-constructor-alias.c
new file mode 100644
--- /dev/null
+++ b/clang/test/Driver/aix-constructor-alias.c
@@ -0,0 +1,7 @@
+// Check that we don't pass -mconstructor-aliases when compiling for AIX.
+
+// RUN: %clang -### -target powerpc-ibm-aix7.1.0.0 %s -c -o %t.o 2>&1 \
+// RUN:   | FileCheck %s
+// RUN: %clang -### -target powerpc64-ibm-aix7.1.0.0 %s -c -o %t.o 2>&1 \
+// RUN:   | FileCheck %s
+// CHECK-NOT: "-mconstructor-aliases"
diff --git a/llvm/lib/Target/PowerPC/PPCAsmPrinter.cpp b/llvm/lib/Target/PowerPC/PPCAsmPrinter.cpp
--- a/llvm/lib/Target/PowerPC/PPCAsmPrinter.cpp
+++ b/llvm/lib/Target/PowerPC/PPCAsmPrinter.cpp
@@ -155,6 +155,14 @@
 
   StringRef getPassName() const override { return "AIX PPC Assembly Printer"; }
 
+  bool doInitialization(Module &M) override {
+    if (M.alias_size() > 0u)
+      report_fatal_error(
+          "module has aliases, which LLVM does not yet support for AIX");
+
+    return PPCAsmPrinter::doInitialization(M);
+  }
+
   void SetupMachineFunction(MachineFunction &MF) override;
 
   void emitGlobalVariable(const GlobalVariable *GV) override;
diff --git a/llvm/test/CodeGen/PowerPC/aix-alias.ll b/llvm/test/CodeGen/PowerPC/aix-alias.ll
new file mode 100644
--- /dev/null
+++ b/llvm/test/CodeGen/PowerPC/aix-alias.ll
@@ -0,0 +1,10 @@
+; RUN: not --crash llc < %s -mtriple powerpc-ibm-aix-xcoff 2>&1 | FileCheck %s
+; RUN: not --crash llc < %s -mtriple powerpc64-ibm-aix-xcoff 2>&1 | FileCheck %s
+
+; Check that, while generation of aliases on AIX remains unimplemented, llc dies
+; with an appropriate message instead of generating incorrect output when an
+; alias is encountered.
+
+define i32 @a() { ret i32 0 }
+; CHECK: ERROR: module has aliases
+@b = internal alias i32 (), i32 ()* @a