From 3b687020f5a628a733147c2f71ebdd7e3554e30c Mon Sep 17 00:00:00 2001
From: Richard Smith <richard-llvm@metafoo.co.uk>
Date: Mon, 19 Dec 2016 23:59:34 +0000
Subject: [PATCH] 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.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@290146 91177308-0d34-0410-b5e6-96231b3b80d8
---
include/clang/Basic/Builtins.def | 4 ++--
lib/AST/ASTContext.cpp | 4 ++--
lib/Sema/SemaChecking.cpp | 4 +++-
lib/Sema/SemaExceptionSpec.cpp | 13 +++++++------
test/Sema/vfprintf-invalid-redecl.c | 2 +-
test/Sema/vfprintf-valid-redecl.c | 8 +++++---
test/SemaCXX/builtins.cpp | 11 ++++++++++-
7 files changed, 30 insertions(+), 16 deletions(-)
diff --git a/include/clang/Basic/Builtins.def b/include/clang/Basic/Builtins.def
index 731d856548..ec0a2796ec 100644
--- a/include/clang/Basic/Builtins.def
+++ b/include/clang/Basic/Builtins.def
@@ -702,7 +702,7 @@ BUILTIN(__atomic_is_lock_free, "izvCD*", "n")
#undef ATOMIC_BUILTIN
// Non-overloaded atomic builtins.
-BUILTIN(__sync_synchronize, "v.", "n")
+BUILTIN(__sync_synchronize, "v", "n")
// GCC does not support these, they are a Clang extension.
BUILTIN(__sync_fetch_and_min, "iiD*i", "n")
BUILTIN(__sync_fetch_and_max, "iiD*i", "n")
@@ -813,7 +813,7 @@ LIBBUILTIN(fprintf, "iP*cC*.", "fp:1:", "stdio.h", ALL_LANGUAGES)
LIBBUILTIN(snprintf, "ic*zcC*.", "fp:2:", "stdio.h", ALL_LANGUAGES)
LIBBUILTIN(sprintf, "ic*cC*.", "fp:1:", "stdio.h", ALL_LANGUAGES)
LIBBUILTIN(vprintf, "icC*a", "fP:0:", "stdio.h", ALL_LANGUAGES)
-LIBBUILTIN(vfprintf, "i.", "fP:1:", "stdio.h", ALL_LANGUAGES)
+LIBBUILTIN(vfprintf, "iP*cC*a", "fP:1:", "stdio.h", ALL_LANGUAGES)
LIBBUILTIN(vsnprintf, "ic*zcC*a", "fP:2:", "stdio.h", ALL_LANGUAGES)
LIBBUILTIN(vsprintf, "ic*cC*a", "fP:1:", "stdio.h", ALL_LANGUAGES)
LIBBUILTIN(scanf, "icC*R.", "fs:0:", "stdio.h", ALL_LANGUAGES)
diff --git a/lib/AST/ASTContext.cpp b/lib/AST/ASTContext.cpp
index 0ad663fdf9..4abca4ce5d 100644
--- a/lib/AST/ASTContext.cpp
+++ b/lib/AST/ASTContext.cpp
@@ -8729,8 +8729,8 @@ QualType ASTContext::GetBuiltinType(unsigned Id,
bool Variadic = (TypeStr[0] == '.');
- // We really shouldn't be making a no-proto type here, especially in C++.
- if (ArgTypes.empty() && Variadic)
+ // We really shouldn't be making a no-proto type here.
+ if (ArgTypes.empty() && Variadic && !getLangOpts().CPlusPlus)
return getFunctionNoProtoType(ResType, EI);
FunctionProtoType::ExtProtoInfo EPI;
diff --git a/lib/Sema/SemaChecking.cpp b/lib/Sema/SemaChecking.cpp
index 450e2789c7..9c90295923 100644
--- a/lib/Sema/SemaChecking.cpp
+++ b/lib/Sema/SemaChecking.cpp
@@ -2448,7 +2448,9 @@ void Sema::checkCall(NamedDecl *FDecl, const FunctionProtoType *Proto,
// Refuse POD arguments that weren't caught by the format string
// checks above.
- if (CallType != VariadicDoesNotApply) {
+ auto *FD = dyn_cast_or_null<FunctionDecl>(FDecl);
+ if (CallType != VariadicDoesNotApply &&
+ (!FD || FD->getBuiltinID() != Builtin::BI__noop)) {
unsigned NumParams = Proto ? Proto->getNumParams()
: FDecl && isa<FunctionDecl>(FDecl)
? cast<FunctionDecl>(FDecl)->getNumParams()
diff --git a/lib/Sema/SemaExceptionSpec.cpp b/lib/Sema/SemaExceptionSpec.cpp
index 781f78018b..2ac2aca6f6 100644
--- a/lib/Sema/SemaExceptionSpec.cpp
+++ b/lib/Sema/SemaExceptionSpec.cpp
@@ -288,14 +288,15 @@ bool Sema::CheckEquivalentExceptionSpec(FunctionDecl *Old, FunctionDecl *New) {
// The new function declaration is only missing an empty exception
// specification "throw()". If the throw() specification came from a
// function in a system header that has C linkage, just add an empty
- // exception specification to the "new" declaration. This is an
- // egregious workaround for glibc, which adds throw() specifications
- // to many libc functions as an optimization. Unfortunately, that
- // optimization isn't permitted by the C++ standard, so we're forced
- // to work around it here.
+ // exception specification to the "new" declaration. Note that C library
+ // implementations are permitted to add these nothrow exception
+ // specifications.
+ //
+ // Likewise if the old function is a builtin.
if (MissingEmptyExceptionSpecification && NewProto &&
(Old->getLocation().isInvalid() ||
- Context.getSourceManager().isInSystemHeader(Old->getLocation())) &&
+ Context.getSourceManager().isInSystemHeader(Old->getLocation()) ||
+ Old->getBuiltinID()) &&
Old->isExternC()) {
New->setType(Context.getFunctionType(
NewProto->getReturnType(), NewProto->getParamTypes(),
diff --git a/test/Sema/vfprintf-invalid-redecl.c b/test/Sema/vfprintf-invalid-redecl.c
index cbf47a69a9..f06b1b6d21 100644
--- a/test/Sema/vfprintf-invalid-redecl.c
+++ b/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/test/Sema/vfprintf-valid-redecl.c b/test/Sema/vfprintf-valid-redecl.c
index 8ed18786ab..eb5c4d3307 100644
--- a/test/Sema/vfprintf-valid-redecl.c
+++ b/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/test/SemaCXX/builtins.cpp b/test/SemaCXX/builtins.cpp
index 69bdfa6145..f26931b55b 100644
--- a/test/SemaCXX/builtins.cpp
+++ b/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}}
+}
--
2.40.0