Change the representation of builtin functions in the AST

(__builtin_* etc.) so that it isn't possible to take their address.
Specifically, introduce a new type to represent a reference to a builtin
function, and a new cast kind to convert it to a function pointer in the
operand of a call.  Fixes PR13195.

llvm-svn: 162962

1 files changed, 13 insertions, 0 deletions

diff --git a/clang/test/SemaCXX/builtins.cpp b/clang/test/SemaCXX/builtins.cpp
index 568ba5dde12..6b055cff640 100644
--- a/clang/test/SemaCXX/builtins.cpp
+++ b/clang/test/SemaCXX/builtins.cpp
@@ -7,3 +7,16 @@ void f() {
 }
 
 void a() { __builtin_va_list x, y; ::__builtin_va_copy(x, y); }
+
+// <rdar://problem/10063539>
+template<int (*Compare)(const char *s1, const char *s2)>
+int equal(const char *s1, const char *s2) {
+  return Compare(s1, s2) == 0;
+}
+// FIXME: Our error recovery here sucks
+template int equal<&__builtin_strcmp>(const char*, const char*); // expected-error {{builtin functions must be directly called}} expected-error {{expected unqualified-id}} expected-error {{expected ')'}} expected-note {{to match this '('}}
+
+// PR13195
+void f2() {
+  __builtin_isnan; // expected-error {{builtin functions must be directly called}}
+}