[clang] f706486 - Fix for crash in __builtin_return_address in template context.

[Sunil Srivastava via cfe-commits]

Author: Sunil Srivastava
Date: 2021-01-12T12:37:18-08:00
New Revision: f706486eaf07020b11f2088274c757e4070fe6d1

URL: https://github.com/llvm/llvm-project/commit/f706486eaf07020b11f2088274c757e4070fe6d1
DIFF: https://github.com/llvm/llvm-project/commit/f706486eaf07020b11f2088274c757e4070fe6d1.diff

LOG: Fix for crash in __builtin_return_address in template context.

The check for argument value needs to be guarded by !isValueDependent().

Differential Revision: https://reviews.llvm.org/D94438

Added: 
    

Modified: 
    clang/lib/Sema/SemaChecking.cpp
    clang/test/Sema/builtin-returnaddress.c

Removed: 
    


################################################################################
diff  --git a/clang/lib/Sema/SemaChecking.cpp b/clang/lib/Sema/SemaChecking.cpp
index 15b5934224f0..2d3d36f4adad 100644
--- a/clang/lib/Sema/SemaChecking.cpp
+++ b/clang/lib/Sema/SemaChecking.cpp
@@ -1943,7 +1943,8 @@ Sema::CheckBuiltinFunctionCall(FunctionDecl *FDecl, unsigned BuiltinID,
     // -Wframe-address warning if non-zero passed to builtin
     // return/frame address.
     Expr::EvalResult Result;
-    if (TheCall->getArg(0)->EvaluateAsInt(Result, getASTContext()) &&
+    if (!TheCall->getArg(0)->isValueDependent() &&
+        TheCall->getArg(0)->EvaluateAsInt(Result, getASTContext()) &&
         Result.Val.getInt() != 0)
       Diag(TheCall->getBeginLoc(), diag::warn_frame_address)
           << ((BuiltinID == Builtin::BI__builtin_return_address)

diff  --git a/clang/test/Sema/builtin-returnaddress.c b/clang/test/Sema/builtin-returnaddress.c
index 3ebbdc6048d8..16d2a517ac12 100644
--- a/clang/test/Sema/builtin-returnaddress.c
+++ b/clang/test/Sema/builtin-returnaddress.c
@@ -1,5 +1,6 @@
 // RUN: %clang_cc1 -fsyntax-only -Wframe-address -verify %s
 // RUN: %clang_cc1 -fsyntax-only -Wmost -verify %s
+// RUN: %clang_cc1 -x c++ -fsyntax-only -Wframe-address -verify %s
 
 void* a(unsigned x) {
 return __builtin_return_address(0);
@@ -17,3 +18,14 @@ void* d(unsigned x) {
 return __builtin_frame_address(1); // expected-warning{{calling '__builtin_frame_address' with a nonzero argument is unsafe}}
 }
 
+#ifdef __cplusplus
+template<int N> void *RA()
+{
+  return __builtin_return_address(N); // expected-warning{{calling '__builtin_return_address' with a nonzero argument is unsafe}}
+}
+
+void *foo()
+{
+ return RA<2>(); // expected-note{{in instantiation of function template specialization 'RA<2>' requested here}}
+}
+#endif