diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp index 1243ce50ec8dfe..ce28d741225e9e 100644 --- a/clang/lib/CodeGen/CodeGenModule.cpp +++ b/clang/lib/CodeGen/CodeGenModule.cpp @@ -1909,9 +1909,15 @@ void CodeGenModule::SetFunctionAttributes(GlobalDecl GD, llvm::Function *F, F->setSection(SA->getName()); // If we plan on emitting this inline builtin, we can't treat it as a builtin. - if (FD->isInlineBuiltinDeclaration() && shouldEmitFunction(FD)) { - F->addAttribute(llvm::AttributeList::FunctionIndex, - llvm::Attribute::NoBuiltin); + if (FD->isInlineBuiltinDeclaration()) { + const FunctionDecl *FDBody; + bool HasBody = FD->hasBody(FDBody); + (void)HasBody; + assert(HasBody && "Inline builtin declarations should always have an " + "available body!"); + if (shouldEmitFunction(FDBody)) + F->addAttribute(llvm::AttributeList::FunctionIndex, + llvm::Attribute::NoBuiltin); } if (FD->isReplaceableGlobalAllocationFunction()) { diff --git a/clang/test/CodeGen/memcpy-no-nobuiltin-if-not-emitted.cpp b/clang/test/CodeGen/memcpy-no-nobuiltin-if-not-emitted.cpp new file mode 100644 index 00000000000000..d27aa9c5341334 --- /dev/null +++ b/clang/test/CodeGen/memcpy-no-nobuiltin-if-not-emitted.cpp @@ -0,0 +1,16 @@ +// RUN: %clang_cc1 -triple i686-linux-gnu -std=c++11 -S -emit-llvm -o - %s | FileCheck %s +// +// Regression test for the issue reported at +// https://reviews.llvm.org/D78162#1986104 + +typedef unsigned long size_t; + +extern "C" __inline__ __attribute__((__gnu_inline__)) void *memcpy(void *a, const void *b, unsigned c) { + return __builtin_memcpy(a, b, c); +} +void *memcpy(void *, const void *, unsigned); + +// CHECK-LABEL: define void @_Z1av +void a() { (void)memcpy; } + +// CHECK-NOT: nobuiltin