Fix completely bogus types for some builtins:

 * In C++, never create a FunctionNoProtoType for a builtin (fixes C++1z
   crasher from r289754).

 * Fix type of __sync_synchronize to be a no-parameter function rather than a
   varargs function. This matches GCC.

 * Fix type of vfprintf to match its actual type. We gave it a wrong type due
   to PR4290 (apparently autoconf generates invalid code and expects compilers
   to choke it down or it miscompiles the program; the relevant error in clang
   was downgraded to a warning in r122744 to fix other occurrences of this
   autoconf brokenness, so we don't need this workaround any more).

 * Turn off vararg argument checking for __noop, since it's not *really* a
   varargs function. Alternatively we could add custom type checking for it
   and synthesize parameter types matching the actual arguments in each call,
   but that seemed like overkill.

llvm-svn: 290146

3 files changed, 16 insertions, 5 deletions

diff --git a/clang/test/Sema/vfprintf-invalid-redecl.c b/clang/test/Sema/vfprintf-invalid-redecl.c
index cbf47a69a9a..f06b1b6d214 100644
--- a/clang/test/Sema/vfprintf-invalid-redecl.c
+++ b/clang/test/Sema/vfprintf-invalid-redecl.c
@@ -3,4 +3,4 @@
 
 // The following declaration is not compatible with vfprintf(), but make
 // sure this isn't an error: autoconf expects this to build.
-char vfprintf(); // expected-warning {{incompatible redeclaration of library function 'vfprintf'}} expected-note {{'vfprintf' is a builtin}}
+char vfprintf(); // expected-warning {{declaration of built-in function 'vfprintf'}}
diff --git a/clang/test/Sema/vfprintf-valid-redecl.c b/clang/test/Sema/vfprintf-valid-redecl.c
index 8ed18786ab7..eb5c4d33071 100644
--- a/clang/test/Sema/vfprintf-valid-redecl.c
+++ b/clang/test/Sema/vfprintf-valid-redecl.c
@@ -1,16 +1,18 @@
 // RUN: %clang_cc1 %s -fsyntax-only -pedantic -verify
 // RUN: %clang_cc1 %s -fsyntax-only -pedantic -verify -DPREDECLARE
-// expected-no-diagnostics
 
 #ifdef PREDECLARE
 // PR16344
 // Clang has defined 'vfprint' in builtin list. If the following line occurs before any other
 // `vfprintf' in this file, and we getPreviousDecl()->getTypeSourceInfo() on it, then we will
 // get a null pointer since the one in builtin list doesn't has valid TypeSourceInfo.
-int vfprintf(void) { return 0; }
+int vfprintf(void) { return 0; } // expected-warning {{requires inclusion of the header <stdio.h>}}
 #endif
 
 // PR4290
 // The following declaration is compatible with vfprintf, so we shouldn't
-// warn.
+// reject.
 int vfprintf();
+#ifndef PREDECLARE
+// expected-warning@-2 {{requires inclusion of the header <stdio.h>}}
+#endif
diff --git a/clang/test/SemaCXX/builtins.cpp b/clang/test/SemaCXX/builtins.cpp
index 69bdfa61451..f26931b55bd 100644
--- a/clang/test/SemaCXX/builtins.cpp
+++ b/clang/test/SemaCXX/builtins.cpp
@@ -1,4 +1,5 @@
-// RUN: %clang_cc1 %s -fsyntax-only -verify -std=c++11
+// RUN: %clang_cc1 %s -fsyntax-only -verify -std=c++11 -fcxx-exceptions
+// RUN: %clang_cc1 %s -fsyntax-only -verify -std=c++1z -fcxx-exceptions
 typedef const struct __CFString * CFStringRef;
 #define CFSTR __builtin___CFStringMakeConstantString
 
@@ -44,3 +45,11 @@ void no_ms_builtins() {
   __noop(1); // expected-error {{use of undeclared}}
   __debugbreak(); // expected-error {{use of undeclared}}
 }
+
+struct FILE;
+extern "C" int vfprintf(FILE *__restrict, const char *__restrict,
+                        __builtin_va_list va);
+
+void synchronize_args() {
+  __sync_synchronize(0); // expected-error {{too many arguments}}
+}