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

3 files changed, 14 insertions, 13 deletions

diff --git a/clang/test/CodeGenCXX/builtins.cpp b/clang/test/CodeGenCXX/builtins.cpp
index 4542563717a..0629c31015c 100644
--- a/clang/test/CodeGenCXX/builtins.cpp
+++ b/clang/test/CodeGenCXX/builtins.cpp
@@ -7,15 +7,3 @@ int main() {
   // CHECK: call signext i8 @memmove()
   return memmove();
 }
-
-// <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;
-}
-
-// CHECK: define weak_odr i32 @_Z5equalIXadL_Z16__builtin_strcmpPKcS1_EEEiS1_S1_
-// CHECK: call i32 @strcmp
-template int equal<&__builtin_strcmp>(const char*, const char*);
-
diff --git a/clang/test/Parser/builtin_classify_type.c b/clang/test/Parser/builtin_classify_type.c
index a7c08555c90..ff483b20974 100644
--- a/clang/test/Parser/builtin_classify_type.c
+++ b/clang/test/Parser/builtin_classify_type.c
@@ -10,7 +10,7 @@ int main() {
 
   static int ary[__builtin_classify_type(a)];
   static int ary2[(__builtin_classify_type)(a)]; // expected-error{{variable length array declaration can not have 'static' storage duration}}
-  static int ary3[(*__builtin_classify_type)(a)]; // expected-error{{variable length array declaration can not have 'static' storage duration}}
+  static int ary3[(*__builtin_classify_type)(a)]; // expected-error{{builtin functions must be directly called}}
 
   int result;
 
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}}
+}