Index: clang/lib/CodeGen/CodeGenModule.cpp =================================================================== --- clang/lib/CodeGen/CodeGenModule.cpp +++ clang/lib/CodeGen/CodeGenModule.cpp @@ -2651,15 +2651,19 @@ namespace { struct FunctionIsDirectlyRecursive : public ConstStmtVisitor { + const FunctionDecl *OriginalFD; const StringRef Name; const Builtin::Context &BI; - FunctionIsDirectlyRecursive(StringRef N, const Builtin::Context &C) - : Name(N), BI(C) {} + FunctionIsDirectlyRecursive(const FunctionDecl *OriginalFD, StringRef N, + const Builtin::Context &C) + : OriginalFD(OriginalFD), Name(N), BI(C) {} bool VisitCallExpr(const CallExpr *E) { const FunctionDecl *FD = E->getDirectCallee(); if (!FD) return false; + if (FD == OriginalFD) + return true; AsmLabelAttr *Attr = FD->getAttr(); if (Attr && Name == Attr->getLabel()) return true; @@ -2762,7 +2766,7 @@ Name = FD->getName(); } - FunctionIsDirectlyRecursive Walker(Name, Context.BuiltinInfo); + FunctionIsDirectlyRecursive Walker(FD, Name, Context.BuiltinInfo); const Stmt *Body = FD->getBody(); return Body ? Walker.Visit(Body) : false; } Index: clang/test/CodeGen/memcpy-no-emission-trivial-recursion.c =================================================================== --- /dev/null +++ clang/test/CodeGen/memcpy-no-emission-trivial-recursion.c @@ -0,0 +1,23 @@ +// RUN: %clang_cc1 -triple x86_64-unknown-unknown -S -emit-llvm -o - %s | FileCheck %s +// +// Verifies that clang doesn't emit trivially-recursive extern inline functions. + +typedef unsigned long size_t; + +// always_inline is used so clang will emit any available_externally function in +// -O0. +#define AVAILABLE_EXTERNALLY extern inline __attribute__((always_inline)) \ + __attribute__((gnu_inline)) + +void some_other_fn(void); + +AVAILABLE_EXTERNALLY void *some_fn() { + some_other_fn(); + return some_fn(); +} + +// CHECK-LABEL: define void @foo +void foo() { + // CHECK-NOT: call void @some_other_fn + some_fn(); +}