[clang] c3fe8dd - Allow -Wno-gnu to silence GNU extensions related to pointer arithmetic
Aaron Ballman via cfe-commits
cfe-commits at lists.llvm.org
Tue Mar 22 10:15:28 PDT 2022
Author: Aaron Ballman
Date: 2022-03-22T13:15:13-04:00
New Revision: c3fe8ddd8385832fde9f16a261908afbaf9878a4
URL: https://github.com/llvm/llvm-project/commit/c3fe8ddd8385832fde9f16a261908afbaf9878a4
DIFF: https://github.com/llvm/llvm-project/commit/c3fe8ddd8385832fde9f16a261908afbaf9878a4.diff
LOG: Allow -Wno-gnu to silence GNU extensions related to pointer arithmetic
These diagnostics were added to a diagnostic group, but that diagnostic
group was not under -Wgnu. I've now split them into their own
diagnostic group that is added both to the original group (so user's
currently opting in or out of these should not see a change) and under
the -Wgnu group so that -Wno-gnu can be used to disable all GNU
extension diagnostics. This fixes Issue 54444.
Added:
Modified:
clang/docs/ReleaseNotes.rst
clang/include/clang/Basic/DiagnosticGroups.td
clang/include/clang/Basic/DiagnosticSemaKinds.td
clang/test/Sema/pointer-addition.c
Removed:
################################################################################
diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst
index d7ff8699f6ca4..9864019fda09b 100644
--- a/clang/docs/ReleaseNotes.rst
+++ b/clang/docs/ReleaseNotes.rst
@@ -63,6 +63,8 @@ Bug Fixes
This fixes `Issue 53742 <https://github.com/llvm/llvm-project/issues/53742>`_.
- We now ignore full expressions when traversing cast subexpressions. This
fixes `Issue 53044 <https://github.com/llvm/llvm-project/issues/53044>`_.
+- Allow `-Wno-gnu` to silence GNU extension diagnostics for pointer arithmetic
+ diagnostics. Fixes `Issue 54444 <https://github.com/llvm/llvm-project/issues/54444>`_.
Improvements to Clang's diagnostics
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
diff --git a/clang/include/clang/Basic/DiagnosticGroups.td b/clang/include/clang/Basic/DiagnosticGroups.td
index 3f14fa32597d9..eb73732838667 100644
--- a/clang/include/clang/Basic/DiagnosticGroups.td
+++ b/clang/include/clang/Basic/DiagnosticGroups.td
@@ -502,7 +502,9 @@ def NonPODVarargs : DiagGroup<"non-pod-varargs">;
def ClassVarargs : DiagGroup<"class-varargs", [NonPODVarargs]>;
def : DiagGroup<"nonportable-cfstrings">;
def NonVirtualDtor : DiagGroup<"non-virtual-dtor">;
-def NullPointerArithmetic : DiagGroup<"null-pointer-arithmetic">;
+def GNUNullPointerArithmetic : DiagGroup<"gnu-null-pointer-arithmetic">;
+def NullPointerArithmetic
+ : DiagGroup<"null-pointer-arithmetic", [GNUNullPointerArithmetic]>;
def NullPointerSubtraction : DiagGroup<"null-pointer-subtraction">;
def : DiagGroup<"effc++", [NonVirtualDtor]>;
def OveralignedType : DiagGroup<"over-aligned">;
@@ -550,7 +552,9 @@ def UnalignedAccess : DiagGroup<"unaligned-access">;
def PessimizingMove : DiagGroup<"pessimizing-move">;
def ReturnStdMove : DiagGroup<"return-std-move">;
-def PointerArith : DiagGroup<"pointer-arith">;
+def GNUPointerArith : DiagGroup<"gnu-pointer-arith">;
+def PointerArith : DiagGroup<"pointer-arith", [GNUPointerArith]>;
+
def PoundWarning : DiagGroup<"#warnings">;
def PoundPragmaMessage : DiagGroup<"#pragma-messages">,
DiagCategory<"#pragma message Directive">;
@@ -1105,12 +1109,13 @@ def GNU : DiagGroup<"gnu", [GNUAlignofExpression, GNUAnonymousStruct,
VLAExtension, GNUFlexibleArrayInitializer,
GNUFlexibleArrayUnionMember, GNUFoldingConstant,
GNUImaginaryConstant, GNUIncludeNext,
- GNULabelsAsValue,
- RedeclaredClassMember, GNURedeclaredEnum,
- GNUStatementExpression, GNUStaticFloatInit,
- GNUStringLiteralOperatorTemplate,
- GNUUnionCast, GNUVariableSizedTypeNotAtEnd,
- ZeroLengthArray, GNUZeroLineDirective,
+ GNULabelsAsValue, GNUNullPointerArithmetic,
+ GNUPointerArith, RedeclaredClassMember,
+ GNURedeclaredEnum, GNUStatementExpression,
+ GNUStaticFloatInit,
+ GNUStringLiteralOperatorTemplate, GNUUnionCast,
+ GNUVariableSizedTypeNotAtEnd, ZeroLengthArray,
+ GNUZeroLineDirective,
GNUZeroVariadicMacroArguments]>;
// A warning group for warnings about code that clang accepts but gcc doesn't.
def GccCompat : DiagGroup<"gcc-compat">;
diff --git a/clang/include/clang/Basic/DiagnosticSemaKinds.td b/clang/include/clang/Basic/DiagnosticSemaKinds.td
index e6b11c943a705..fea7461e2dc99 100644
--- a/clang/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/clang/include/clang/Basic/DiagnosticSemaKinds.td
@@ -6464,9 +6464,9 @@ def warn_sub_ptr_zero_size_types : Warning<
def warn_pointer_arith_null_ptr : Warning<
"performing pointer arithmetic on a null pointer has undefined behavior%select{| if the offset is nonzero}0">,
InGroup<NullPointerArithmetic>, DefaultIgnore;
-def warn_gnu_null_ptr_arith : Warning<
+def warn_gnu_null_ptr_arith : Extension<
"arithmetic on a null pointer treated as a cast from integer to pointer is a GNU extension">,
- InGroup<NullPointerArithmetic>, DefaultIgnore;
+ InGroup<GNUNullPointerArithmetic>;
def warn_pointer_sub_null_ptr : Warning<
"performing pointer subtraction with a null pointer %select{has|may have}0 undefined behavior">,
InGroup<NullPointerSubtraction>, DefaultIgnore;
@@ -6612,7 +6612,8 @@ def err_subscript_incomplete_or_sizeless_type : Error<
def err_dereference_incomplete_type : Error<
"dereference of pointer to incomplete type %0">;
def ext_gnu_subscript_void_type : Extension<
- "subscript of a pointer to void is a GNU extension">, InGroup<PointerArith>;
+ "subscript of a pointer to void is a GNU extension">,
+ InGroup<GNUPointerArith>;
def err_typecheck_member_reference_struct_union : Error<
"member reference base type %0 is not a structure or union">;
def err_typecheck_member_reference_ivar : Error<
@@ -7133,11 +7134,11 @@ def err_duplicate_property : Error<
"property has a previous declaration">;
def ext_gnu_void_ptr : Extension<
"arithmetic on%select{ a|}0 pointer%select{|s}0 to void is a GNU extension">,
- InGroup<PointerArith>;
+ InGroup<GNUPointerArith>;
def ext_gnu_ptr_func_arith : Extension<
"arithmetic on%select{ a|}0 pointer%select{|s}0 to%select{ the|}2 function "
"type%select{|s}2 %1%select{| and %3}2 is a GNU extension">,
- InGroup<PointerArith>;
+ InGroup<GNUPointerArith>;
def err_readonly_message_assignment : Error<
"assigning to 'readonly' return result of an Objective-C message not allowed">;
def ext_integer_increment_complex : Extension<
diff --git a/clang/test/Sema/pointer-addition.c b/clang/test/Sema/pointer-addition.c
index 562f05340f7cb..725d7123cf1ec 100644
--- a/clang/test/Sema/pointer-addition.c
+++ b/clang/test/Sema/pointer-addition.c
@@ -1,6 +1,7 @@
-// RUN: %clang_cc1 %s -fsyntax-only -verify -pedantic -Wextra -std=c11
-// RUN: %clang_cc1 %s -fsyntax-only -triple i686-unknown-unknown -verify -pedantic -Wextra -std=c11
-// RUN: %clang_cc1 %s -fsyntax-only -triple x86_64-unknown-unknown -verify -pedantic -Wextra -std=c11
+// RUN: %clang_cc1 %s -fsyntax-only -verify=gnu,expected -pedantic -Wextra -std=c11
+// RUN: %clang_cc1 %s -fsyntax-only -triple i686-unknown-unknown -verify=gnu,expected -pedantic -Wextra -std=c11
+// RUN: %clang_cc1 %s -fsyntax-only -triple x86_64-unknown-unknown -verify=gnu,expected -pedantic -Wextra -std=c11
+// RUN: %clang_cc1 %s -fsyntax-only -verify -pedantic -Wextra -Wno-gnu -std=c11
#include <stdint.h>
@@ -10,22 +11,22 @@ void a(S* b, void* c) {
void (*fp)(int) = 0;
b++; // expected-error {{arithmetic on a pointer to an incomplete type}}
b += 1; // expected-error {{arithmetic on a pointer to an incomplete type}}
- c++; // expected-warning {{arithmetic on a pointer to void is a GNU extension}}
- c += 1; // expected-warning {{arithmetic on a pointer to void is a GNU extension}}
- c--; // expected-warning {{arithmetic on a pointer to void is a GNU extension}}
- c -= 1; // expected-warning {{arithmetic on a pointer to void is a GNU extension}}
- (void) c[1]; // expected-warning {{subscript of a pointer to void is a GNU extension}}
+ c++; // gnu-warning {{arithmetic on a pointer to void is a GNU extension}}
+ c += 1; // gnu-warning {{arithmetic on a pointer to void is a GNU extension}}
+ c--; // gnu-warning {{arithmetic on a pointer to void is a GNU extension}}
+ c -= 1; // gnu-warning {{arithmetic on a pointer to void is a GNU extension}}
+ (void) c[1]; // gnu-warning {{subscript of a pointer to void is a GNU extension}}
b = 1+b; // expected-error {{arithmetic on a pointer to an incomplete type}}
/* The next couple tests are only pedantic warnings in gcc */
void (*d)(S*,void*) = a;
- d += 1; // expected-warning {{arithmetic on a pointer to the function type 'void (S *, void *)' (aka 'void (struct S *, void *)') is a GNU extension}}
- d++; // expected-warning {{arithmetic on a pointer to the function type 'void (S *, void *)' (aka 'void (struct S *, void *)') is a GNU extension}}
- d--; // expected-warning {{arithmetic on a pointer to the function type 'void (S *, void *)' (aka 'void (struct S *, void *)') is a GNU extension}}
- d -= 1; // expected-warning {{arithmetic on a pointer to the function type 'void (S *, void *)' (aka 'void (struct S *, void *)') is a GNU extension}}
- (void)(1 + d); // expected-warning {{arithmetic on a pointer to the function type 'void (S *, void *)' (aka 'void (struct S *, void *)') is a GNU extension}}
+ d += 1; // gnu-warning {{arithmetic on a pointer to the function type 'void (S *, void *)' (aka 'void (struct S *, void *)') is a GNU extension}}
+ d++; // gnu-warning {{arithmetic on a pointer to the function type 'void (S *, void *)' (aka 'void (struct S *, void *)') is a GNU extension}}
+ d--; // gnu-warning {{arithmetic on a pointer to the function type 'void (S *, void *)' (aka 'void (struct S *, void *)') is a GNU extension}}
+ d -= 1; // gnu-warning {{arithmetic on a pointer to the function type 'void (S *, void *)' (aka 'void (struct S *, void *)') is a GNU extension}}
+ (void)(1 + d); // gnu-warning {{arithmetic on a pointer to the function type 'void (S *, void *)' (aka 'void (struct S *, void *)') is a GNU extension}}
e++; // expected-error {{arithmetic on a pointer to an incomplete type}}
intptr_t i = (intptr_t)b;
- char *f = (char*)0 + i; // expected-warning {{arithmetic on a null pointer treated as a cast from integer to pointer is a GNU extension}}
+ char *f = (char*)0 + i; // gnu-warning {{arithmetic on a null pointer treated as a cast from integer to pointer is a GNU extension}}
// Cases that don't match the GNU inttoptr idiom get a
diff erent warning.
f = (char*)0 - i; // expected-warning {{performing pointer arithmetic on a null pointer has undefined behavior}}
int *g = (int*)0 + i; // expected-warning {{performing pointer arithmetic on a null pointer has undefined behavior}}
More information about the cfe-commits
mailing list