Author: rnk
Date: Tue Sep 10 18:01:06 2019
New Revision: 371581
URL: http://llvm.org/viewvc/llvm-project?rev=371581&view=rev
Log:
Emit -Wmicrosoft-enum-value warning instead of error in MS ABI
Summary:
The first NFC change is to replace a getCXXABI().isMicrosoft() check
with getTriple().isWindowsMSVCEnvironment(). This code takes effect in
non-C++ compilations, so it doesn't make sense to check the C++ ABI. In
the MS ABI, enums are always considered to be "complete" because the
underlying type of an unfixed enum will always be 'int'. This behavior
was moved from -fms-compatibility to MS ABI back in r249656.
The second change is functional, and it downgrades an error to a warning
when the MS ABI is used rather than only under -fms-compatibility. The
reasoning is that it's unreasonable for the following code to reject the
following code for all MS ABI targets with -fno-ms-compatibility:
enum Foo { Foo_Val = 0xDEADBEEF };
This is valid code for any other target, but in the MS ABI, Foo_Val just
happens to be negative. With this change, clang emits a
-Wmicrosoft-enum-value warning on this code, but compiles it without
error.
Fixes PR38478
Reviewers: hans, rsmith, STL_MSFT
Subscribers: cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D67304
Modified:
cfe/trunk/lib/Sema/SemaDecl.cpp
cfe/trunk/test/Sema/MicrosoftCompatibility.c
Modified: cfe/trunk/lib/Sema/SemaDecl.cpp
URL:
http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaDecl.cpp?rev=371581&r1=371580&r2=371581&view=diff
==============================================================================
--- cfe/trunk/lib/Sema/SemaDecl.cpp (original)
+++ cfe/trunk/lib/Sema/SemaDecl.cpp Tue Sep 10 18:01:06 2019
@@ -14723,7 +14723,7 @@ Decl *Sema::ActOnTag(Scope *S, unsigned
UPPC_FixedUnderlyingType))
EnumUnderlying = Context.IntTy.getTypePtr();
- } else if (Context.getTargetInfo().getCXXABI().isMicrosoft()) {
+ } else if (Context.getTargetInfo().getTriple().isWindowsMSVCEnvironment())
{
// For MSVC ABI compatibility, unfixed enums must use an underlying type
// of 'int'. However, if this is an unfixed forward declaration, don't
set
// the underlying type unless the user enables -fms-compatibility. This
@@ -16850,8 +16850,7 @@ EnumConstantDecl *Sema::CheckEnumConstan
if (Enum->isDependentType() || Val->isTypeDependent())
EltTy = Context.DependentTy;
else {
- if (getLangOpts().CPlusPlus11 && Enum->isFixed() &&
- !getLangOpts().MSVCCompat) {
+ if (getLangOpts().CPlusPlus11 && Enum->isFixed()) {
// C++11 [dcl.enum]p5: If the underlying type is fixed, [...] the
// constant-expression in the enumerator-definition shall be a
converted
// constant expression of the underlying type.
@@ -16876,15 +16875,19 @@ EnumConstantDecl *Sema::CheckEnumConstan
// we perform a non-narrowing conversion as part of converted
constant
// expression checking.
if (!isRepresentableIntegerValue(Context, EnumVal, EltTy)) {
- if (getLangOpts().MSVCCompat) {
+ if (Context.getTargetInfo()
+ .getTriple()
+ .isWindowsMSVCEnvironment()) {
Diag(IdLoc, diag::ext_enumerator_too_large) << EltTy;
- Val = ImpCastExprToType(Val, EltTy, CK_IntegralCast).get();
- } else
+ } else {
Diag(IdLoc, diag::err_enumerator_too_large) << EltTy;
- } else
- Val = ImpCastExprToType(Val, EltTy,
- EltTy->isBooleanType() ?
- CK_IntegralToBoolean : CK_IntegralCast)
+ }
+ }
+
+ // Cast to the underlying type.
+ Val = ImpCastExprToType(Val, EltTy,
+ EltTy->isBooleanType() ? CK_IntegralToBoolean
+ : CK_IntegralCast)
.get();
} else if (getLangOpts().CPlusPlus) {
// C++11 [dcl.enum]p5:
Modified: cfe/trunk/test/Sema/MicrosoftCompatibility.c
URL:
http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Sema/MicrosoftCompatibility.c?rev=371581&r1=371580&r2=371581&view=diff
==============================================================================
--- cfe/trunk/test/Sema/MicrosoftCompatibility.c (original)
+++ cfe/trunk/test/Sema/MicrosoftCompatibility.c Tue Sep 10 18:01:06 2019
@@ -1,10 +1,18 @@
-// RUN: %clang_cc1 %s -fsyntax-only -Wno-unused-value -Wmicrosoft -verify
-fms-compatibility -triple i686-pc-win32
+// RUN: %clang_cc1 %s -fsyntax-only -Wno-unused-value -Wmicrosoft -verify
-fms-compatibility -DMSVCCOMPAT -triple i686-pc-win32
+// RUN: %clang_cc1 %s -fsyntax-only -Wno-unused-value -Wmicrosoft -verify
-fms-extensions -triple i686-pc-win32
+#ifdef MSVCCOMPAT
enum ENUM1; // expected-warning {{forward references to 'enum' types are a
Microsoft extension}}
enum ENUM1 var1 = 3;
enum ENUM1* var2 = 0;
+#else
+enum ENUM1; // expected-note {{forward declaration of}}
+enum ENUM1 var1 = 3; // expected-error {{variable has incomplete type 'enum
ENUM1'}}
+enum ENUM1* var2 = 0;
+#endif
+// FIXME: The rest of this seems to be controlled by -fms-extensions. Move it.
enum ENUM2 {
ENUM2_a = (enum ENUM2) 4,
ENUM2_b = 0x9FFFFFFF, // expected-warning {{enumerator value is not
representable in the underlying type 'int'}}
@@ -22,4 +30,8 @@ struct __declspec(appdomain) S3 {}; /* e
__declspec(__noreturn__) void f7(void); /* expected-warning {{__declspec
attribute '__noreturn__' is not supported}} */
+#ifdef MSVCCOMPAT
size_t x;
+#else
+size_t x; // expected-error {{unknown type name 'size_t'}}
+#endif
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