From: David Chisnall <csdavec@swan.ac.uk>
Date: Fri, 6 Jan 2012 12:20:19 +0000 (+0000)
Subject: If we are compiling with -fno-builtin then don't do constant folding of
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=843cc5aaed8c1b2e750aeef3ba13959f0ee117cc;p=clang

If we are compiling with -fno-builtin then don't do constant folding of
builtins.

This fixes PR11711.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@147655 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/CodeGen/CGBuiltin.cpp b/lib/CodeGen/CGBuiltin.cpp
index 3e5a6772eb..f462ee62ad 100644
--- a/lib/CodeGen/CGBuiltin.cpp
+++ b/lib/CodeGen/CGBuiltin.cpp
@@ -175,7 +175,8 @@ RValue CodeGenFunction::EmitBuiltinExpr(const FunctionDecl *FD,
                                         unsigned BuiltinID, const CallExpr *E) {
   // See if we can constant fold this builtin.  If so, don't emit it at all.
   Expr::EvalResult Result;
-  if (E->EvaluateAsRValue(Result, CGM.getContext()) &&
+  if (!getContext().getLangOptions().NoBuiltin &&
+      E->EvaluateAsRValue(Result, CGM.getContext()) &&
       !Result.hasSideEffects()) {
     if (Result.Val.isInt())
       return RValue::get(llvm::ConstantInt::get(getLLVMContext(),
diff --git a/test/CodeGen/no-builtin.c b/test/CodeGen/no-builtin.c
new file mode 100644
index 0000000000..ff1c192481
--- /dev/null
+++ b/test/CodeGen/no-builtin.c
@@ -0,0 +1,20 @@
+// RUN: %clang_cc1 -fno-builtin -emit-llvm %s -o - | FileCheck %s
+//
+// Check that -fno-builtin prevents us from constant-folding through builtins
+// (PR11711)
+
+double
+cos(double x)
+{
+  printf("ok\n");
+  exit(0);
+}
+
+int
+main(int argc, char *argv[])
+{
+  cos(1); // CHECK: cos
+  printf("not ok\n");
+  abort();
+}
+