https://github.com/Sirraide updated
https://github.com/llvm/llvm-project/pull/84169
>From f0c1b2d114fc112726b61ec9274ba37cd3c2160b Mon Sep 17 00:00:00 2001
From: Sirraide <aeternalm...@gmail.com>
Date: Wed, 6 Mar 2024 14:50:02 +0100
Subject: [PATCH 1/2] [Clang] [Sema] No longer diagnose type definitions in
`offsetof` in C23 mode
---
.../include/clang/Basic/DiagnosticSemaKinds.td | 4 ++--
clang/lib/Sema/SemaDecl.cpp | 4 +++-
clang/test/C/C2x/n2350.c | 10 +++++-----
clang/test/C/drs/dr4xx.c | 17 ++++++++++-------
4 files changed, 20 insertions(+), 15 deletions(-)
diff --git a/clang/include/clang/Basic/DiagnosticSemaKinds.td
b/clang/include/clang/Basic/DiagnosticSemaKinds.td
index b007ff7d8ccf0f..bdc9cb9cbca2c7 100644
--- a/clang/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/clang/include/clang/Basic/DiagnosticSemaKinds.td
@@ -1732,8 +1732,8 @@ def err_type_defined_in_condition : Error<
def err_type_defined_in_enum : Error<
"%0 cannot be defined in an enumeration">;
def ext_type_defined_in_offsetof : Extension<
- "defining a type within '%select{__builtin_offsetof|offsetof}0' is a Clang "
- "extension">, InGroup<GNUOffsetofExtensions>;
+ "defining a type within '%select{__builtin_offsetof|offsetof}0' is a C23 "
+ "extension">, InGroup<C23>;
def note_pure_virtual_function : Note<
"unimplemented pure virtual method %0 in %1">;
diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
index 6b81ee183cc440..05347ba297c31c 100644
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/lib/Sema/SemaDecl.cpp
@@ -18098,7 +18098,9 @@ Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind
TUK, SourceLocation KWLoc,
cast_or_null<RecordDecl>(PrevDecl));
}
- if (OOK != OOK_Outside && TUK == TUK_Definition && !getLangOpts().CPlusPlus)
+ // Only C23 and later allow defining new types in 'offsetof()'.
+ if (OOK != OOK_Outside && TUK == TUK_Definition && !getLangOpts().CPlusPlus
&&
+ !getLangOpts().C23)
Diag(New->getLocation(), diag::ext_type_defined_in_offsetof)
<< (OOK == OOK_Macro) << New->getSourceRange();
diff --git a/clang/test/C/C2x/n2350.c b/clang/test/C/C2x/n2350.c
index 2f738488a37427..af0ca6d79be5e1 100644
--- a/clang/test/C/C2x/n2350.c
+++ b/clang/test/C/C2x/n2350.c
@@ -5,7 +5,7 @@
// RUN: %clang_cc1 -fsyntax-only -pedantic -Wno-comment -std=c99 -verify %s
// RUN: %clang_cc1 -fsyntax-only -pedantic -Wno-comment -std=c11 -verify %s
// RUN: %clang_cc1 -fsyntax-only -pedantic -Wno-comment -std=c17 -verify %s
-// RUN: %clang_cc1 -fsyntax-only -pedantic -Wno-comment -std=c2x -verify %s
+// RUN: %clang_cc1 -fsyntax-only -pedantic -Wno-comment -std=c2x
-verify=silent %s
// silent-no-diagnostics
@@ -13,10 +13,10 @@
// https://www.open-std.org/jtc1/sc22/wg14/www/docs/n2350.htm
int simple(void) {
return __builtin_offsetof(struct A // cpp-error {{'A' cannot be defined in a
type specifier}} \
- expected-warning {{defining a type
within '__builtin_offsetof' is a Clang extension}}
+ expected-warning {{defining a type
within '__builtin_offsetof' is a C23 extension}}
{
int a;
- struct B // expected-warning {{defining a type within '__builtin_offsetof'
is a Clang extension}}
+ struct B // expected-warning {{defining a type within '__builtin_offsetof'
is a C23 extension}}
{
int c;
int d;
@@ -26,7 +26,7 @@ int simple(void) {
int anonymous_struct(void) {
return __builtin_offsetof(struct // cpp-error-re {{'(unnamed struct at
{{.*}})' cannot be defined in a type specifier}} \
- expected-warning {{defining a type
within '__builtin_offsetof' is a Clang extension}}
+ expected-warning {{defining a type
within '__builtin_offsetof' is a C23 extension}}
{
int a;
int b;
@@ -47,7 +47,7 @@ int struct_in_second_param(void) {
int macro(void) {
return offsetof(struct A // cpp-error {{'A' cannot be defined in a type
specifier}} \
- expected-warning 2 {{defining a type within
'offsetof' is a Clang extension}}
+ expected-warning 2 {{defining a type within
'offsetof' is a C23 extension}}
{
int a;
struct B // verifier seems to think the error is emitted by the macro
diff --git a/clang/test/C/drs/dr4xx.c b/clang/test/C/drs/dr4xx.c
index 30145dcfeef168..83d7b94cd67959 100644
--- a/clang/test/C/drs/dr4xx.c
+++ b/clang/test/C/drs/dr4xx.c
@@ -1,7 +1,7 @@
-/* RUN: %clang_cc1 -std=c89 -verify=expected,c89only -pedantic
-Wno-c11-extensions %s
- RUN: %clang_cc1 -std=c99 -verify=expected -pedantic -Wno-c11-extensions %s
- RUN: %clang_cc1 -std=c11 -verify=expected -pedantic %s
- RUN: %clang_cc1 -std=c17 -verify=expected -pedantic %s
+/* RUN: %clang_cc1 -std=c89 -verify=expected,c89only,pre-c23 -pedantic
-Wno-c11-extensions %s
+ RUN: %clang_cc1 -std=c99 -verify=expected,pre-c23 -pedantic
-Wno-c11-extensions %s
+ RUN: %clang_cc1 -std=c11 -verify=expected,pre-c23 -pedantic %s
+ RUN: %clang_cc1 -std=c17 -verify=expected,pre-c23 -pedantic %s
RUN: %clang_cc1 -std=c2x -verify=expected -pedantic %s
*/
@@ -343,10 +343,13 @@ void dr496(void) {
*/
/* The DR asked a question about whether defining a new type within offsetof
- * is allowed. C2x N2350 made this explicitly undefined behavior, but GCC and
- * Clang both support it as an extension.
+ * is allowed. C23 N2350 had made this explicitly undefined behavior, but
this
+ * was later overturned when C23 DE-137 was accepted, making it well-formed.
+ *
+ * Additionally, GCC and Clang both support it as an extension in pre-C23
+ * mode.
*/
- (void)__builtin_offsetof(struct S { int a; }, a); /*
expected-warning{{defining a type within '__builtin_offsetof' is a Clang
extension}} */
+ (void)__builtin_offsetof(struct S { int a; }, a); /*
pre-c23-warning{{defining a type within '__builtin_offsetof' is a C23
extension}} */
}
/* WG14 DR499: yes
>From ff3d00b63fcb8cf1d336b45a58771f780efaac31 Mon Sep 17 00:00:00 2001
From: Sirraide <aeternalm...@gmail.com>
Date: Wed, 6 Mar 2024 14:53:05 +0100
Subject: [PATCH 2/2] [Clang] Update release notes
---
clang/docs/ReleaseNotes.rst | 3 +++
1 file changed, 3 insertions(+)
diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst
index 0ff4a93b15ea8f..8f730c459967be 100644
--- a/clang/docs/ReleaseNotes.rst
+++ b/clang/docs/ReleaseNotes.rst
@@ -212,6 +212,9 @@ Improvements to Clang's diagnostics
- Clang now diagnoses lambda function expressions being implicitly cast to
boolean values, under ``-Wpointer-bool-conversion``.
Fixes #GH82512.
+- Clang now no longer diagnoses type definitions in ``offsetof`` in C23 mode.
+ Fixes #GH83658.
+
Improvements to Clang's time-trace
----------------------------------
_______________________________________________
cfe-commits mailing list
cfe-commits@lists.llvm.org
https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
