Index: clang/docs/ReleaseNotes.rst =================================================================== --- clang/docs/ReleaseNotes.rst +++ clang/docs/ReleaseNotes.rst @@ -63,6 +63,8 @@ This fixes `Issue 53742 `_. - We now ignore full expressions when traversing cast subexpressions. This fixes `Issue 53044 `_. +- Allow `-Wno-gnu` to silence GNU extension diagnostics for pointer arithmetic + diagnostics. Fixes `Issue 54444 `_. Improvements to Clang's diagnostics ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Index: clang/include/clang/Basic/DiagnosticGroups.td =================================================================== --- clang/include/clang/Basic/DiagnosticGroups.td +++ clang/include/clang/Basic/DiagnosticGroups.td @@ -502,7 +502,9 @@ 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 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 @@ 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">; Index: clang/include/clang/Basic/DiagnosticSemaKinds.td =================================================================== --- clang/include/clang/Basic/DiagnosticSemaKinds.td +++ clang/include/clang/Basic/DiagnosticSemaKinds.td @@ -6464,9 +6464,9 @@ 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, 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, DefaultIgnore; + InGroup; def warn_pointer_sub_null_ptr : Warning< "performing pointer subtraction with a null pointer %select{has|may have}0 undefined behavior">, InGroup, DefaultIgnore; @@ -6612,7 +6612,8 @@ 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; + "subscript of a pointer to void is a GNU extension">, + InGroup; 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 @@ "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; + InGroup; 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; + InGroup; def err_readonly_message_assignment : Error< "assigning to 'readonly' return result of an Objective-C message not allowed">; def ext_integer_increment_complex : Extension< Index: clang/test/Sema/pointer-addition.c =================================================================== --- clang/test/Sema/pointer-addition.c +++ 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 @@ -10,22 +11,22 @@ 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 different 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}}