[PATCH] Add new warning Wmissing-designated-initializers [PR39589]
Currently the behaviour of Wmissing-field-initializers is inconsistent
between C and C++. The C warning assumes that missing designated
initializers are deliberate, and does not warn. The C++ warning does warn
for missing designated initializers.
This patch changes the behaviour of Wmissing-field-initializers to
universally not warn about missing designated initializers, and adds a new
warning for specifically for missing designated initializers.
NOTE TO MAINTAINERS: This is my first gcc contribution, so I don't have
git write access.
Successfully tested on x86_64-pc-linux-gnu.
PR c/39589
gcc/c-family/ChangeLog:
* c.opt:
gcc/c/ChangeLog:
* c-typeck.cc (pop_init_level):
gcc/cp/ChangeLog:
* typeck2.cc (process_init_constructor_record):
gcc/testsuite/ChangeLog:
* g++.dg/diagnostic/base.C:
* gcc.dg/20011021-1.c:
* gcc.dg/missing-field-init-1.c:
* gcc.dg/pr60784.c:
* g++.dg/warn/missing-designated-initializers-1.C: New test.
* g++.dg/warn/missing-designated-initializers-2.C: New test.
* gcc.dg/missing-designated-initializers-1.c: New test.
* gcc.dg/missing-designated-initializers-2.c: New test.
---
gcc/c-family/c.opt| 4 +++
gcc/c/c-typeck.cc | 36 +++
gcc/cp/typeck2.cc | 20 ---
gcc/testsuite/g++.dg/diagnostic/base.C| 4 +--
.../warn/missing-designated-initializers-1.C | 11 ++
.../warn/missing-designated-initializers-2.C | 11 ++
gcc/testsuite/gcc.dg/20011021-1.c | 4 +--
.../missing-designated-initializers-1.c | 13 +++
.../missing-designated-initializers-2.c | 13 +++
gcc/testsuite/gcc.dg/missing-field-init-1.c | 2 +-
gcc/testsuite/gcc.dg/pr60784.c| 2 +-
11 files changed, 96 insertions(+), 24 deletions(-)
create mode 100644
gcc/testsuite/g++.dg/warn/missing-designated-initializers-1.C
create mode 100644
gcc/testsuite/g++.dg/warn/missing-designated-initializers-2.C
create mode 100644 gcc/testsuite/gcc.dg/missing-designated-initializers-1.c
create mode 100644 gcc/testsuite/gcc.dg/missing-designated-initializers-2.c
diff --git a/gcc/c-family/c.opt b/gcc/c-family/c.opt
index 491aa02e1a3..81e52f1417e 100644
--- a/gcc/c-family/c.opt
+++ b/gcc/c-family/c.opt
@@ -977,6 +977,10 @@ Wmissing-field-initializers
C ObjC C++ ObjC++ Var(warn_missing_field_initializers) Warning
EnabledBy(Wextra)
Warn about missing fields in struct initializers.
+Wmissing-designated-initializers
+C ObjC C++ ObjC++ Var(warn_missing_designated_initializers) Warning
EnabledBy(Wextra)
+Warn about missing designated initialisers in struct initializers.
+
Wmissing-format-attribute
C ObjC C++ ObjC++ Warning Alias(Wsuggest-attribute=format)
;
diff --git a/gcc/c/c-typeck.cc b/gcc/c/c-typeck.cc
index 094e41fa202..72b544e8f67 100644
--- a/gcc/c/c-typeck.cc
+++ b/gcc/c/c-typeck.cc
@@ -9795,7 +9795,7 @@ pop_init_level (location_t loc, int implicit,
}
/* Warn when some struct elements are implicitly initialized to zero. */
- if (warn_missing_field_initializers
+ if ((warn_missing_field_initializers || warn_missing_designated_initializers)
&& constructor_type
&& TREE_CODE (constructor_type) == RECORD_TYPE
&& constructor_unfilled_fields)
@@ -9806,21 +9806,29 @@ pop_init_level (location_t loc, int implicit,
|| integer_zerop (DECL_SIZE (constructor_unfilled_fields
constructor_unfilled_fields = DECL_CHAIN
(constructor_unfilled_fields);
- if (constructor_unfilled_fields
- /* Do not warn if this level of the initializer uses member
- designators; it is likely to be deliberate. */
- && !constructor_designated
- /* Do not warn about initializing with { 0 } or with { }. */
- && !constructor_zeroinit)
- {
- if (warning_at (input_location, OPT_Wmissing_field_initializers,
+ if (constructor_unfilled_fields
+ /* Do not warn about initializing with { 0 } or with { }. */
+ && !constructor_zeroinit)
+ {
+ if (!constructor_designated)
+ {
+ if (warning_at (input_location,
OPT_Wmissing_field_initializers,
"missing initializer for field %qD of %qT",
- constructor_unfilled_fields,
- constructor_type))
- inform (DECL_SOURCE_LOCATION (constructor_unfilled_fields),
+ constructor_unfilled_fields, constructor_type))
+ inform (DECL_SOURCE_LOCATION
(constructor_unfilled_fields),
+ "%qD declared here", constructor_unfilled_fields);
+ }
+ else if (warn_missing_designated_initializers)
+ {
+ if (warning_at (
+
Re: [PATCH] Add new warning Wmissing-designated-initializers [PR39589]
Ping https://gcc.gnu.org/pipermail/gcc-patches/2024-August/661510.html
[PATCH v2] Add new warning Wmissing-designated-initializers [PR39589]
v2 Patch:
* adds proper changelog text
* fixes typo in c.opt
Currently the behaviour of Wmissing-field-initializers is inconsistent
between C and C++. The C warning assumes that missing designated
initializers are deliberate, and does not warn. The C++ warning does warn
for missing designated initializers.
This patch changes the behaviour of Wmissing-field-initializers to
universally not warn about missing designated initializers, and adds a new
warning for specifically for missing designated initializers.
NOTE TO MAINTAINERS: This is my first gcc contribution, so I don't have
git write access.
Successfully tested on x86_64-pc-linux-gnu.
PR c/39589
gcc/c-family/ChangeLog:
* c.opt: Added new option Wmissing-designated-initializers, enabled by
Wextra
gcc/c/ChangeLog:
* c-typeck.cc (pop_init_level): Generate warning for missing designated
initializers rather than always ignore
gcc/cp/ChangeLog:
* typeck2.cc (process_init_constructor_record): Add check if missing
initializer is designated, warn as appropriate
gcc/testsuite/ChangeLog:
* g++.dg/diagnostic/base.C: Change flags
* gcc.dg/20011021-1.c: Fix test, missing designated initializers can
generate a warning now
* gcc.dg/missing-field-init-1.c: Change flags
* gcc.dg/pr60784.c: Change flags
* g++.dg/warn/missing-designated-initializers-1.C: New test.
* g++.dg/warn/missing-designated-initializers-2.C: New test.
* gcc.dg/missing-designated-initializers-1.c: New test.
* gcc.dg/missing-designated-initializers-2.c: New test.
---
gcc/c-family/c.opt| 4 +++
gcc/c/c-typeck.cc | 36 +++
gcc/cp/typeck2.cc | 20 ---
gcc/testsuite/g++.dg/diagnostic/base.C| 4 +--
.../warn/missing-designated-initializers-1.C | 11 ++
.../warn/missing-designated-initializers-2.C | 11 ++
gcc/testsuite/gcc.dg/20011021-1.c | 4 +--
.../missing-designated-initializers-1.c | 13 +++
.../missing-designated-initializers-2.c | 13 +++
gcc/testsuite/gcc.dg/missing-field-init-1.c | 2 +-
gcc/testsuite/gcc.dg/pr60784.c| 2 +-
11 files changed, 96 insertions(+), 24 deletions(-)
create mode 100644
gcc/testsuite/g++.dg/warn/missing-designated-initializers-1.C
create mode 100644
gcc/testsuite/g++.dg/warn/missing-designated-initializers-2.C
create mode 100644 gcc/testsuite/gcc.dg/missing-designated-initializers-1.c
create mode 100644 gcc/testsuite/gcc.dg/missing-designated-initializers-2.c
diff --git a/gcc/c-family/c.opt b/gcc/c-family/c.opt
index 491aa02e1a3..81e52f1417e 100644
--- a/gcc/c-family/c.opt
+++ b/gcc/c-family/c.opt
@@ -977,6 +977,10 @@ Wmissing-field-initializers
C ObjC C++ ObjC++ Var(warn_missing_field_initializers) Warning
EnabledBy(Wextra)
Warn about missing fields in struct initializers.
+Wmissing-designated-initializers
+C ObjC C++ ObjC++ Var(warn_missing_designated_initializers) Warning
EnabledBy(Wextra)
+Warn about missing designated initializers in struct initializers.
+
Wmissing-format-attribute
C ObjC C++ ObjC++ Warning Alias(Wsuggest-attribute=format)
;
diff --git a/gcc/c/c-typeck.cc b/gcc/c/c-typeck.cc
index 094e41fa202..72b544e8f67 100644
--- a/gcc/c/c-typeck.cc
+++ b/gcc/c/c-typeck.cc
@@ -9795,7 +9795,7 @@ pop_init_level (location_t loc, int implicit,
}
/* Warn when some struct elements are implicitly initialized to zero. */
- if (warn_missing_field_initializers
+ if ((warn_missing_field_initializers || warn_missing_designated_initializers)
&& constructor_type
&& TREE_CODE (constructor_type) == RECORD_TYPE
&& constructor_unfilled_fields)
@@ -9806,21 +9806,29 @@ pop_init_level (location_t loc, int implicit,
|| integer_zerop (DECL_SIZE (constructor_unfilled_fields
constructor_unfilled_fields = DECL_CHAIN
(constructor_unfilled_fields);
- if (constructor_unfilled_fields
- /* Do not warn if this level of the initializer uses member
- designators; it is likely to be deliberate. */
- && !constructor_designated
- /* Do not warn about initializing with { 0 } or with { }. */
- && !constructor_zeroinit)
- {
- if (warning_at (input_location, OPT_Wmissing_field_initializers,
+ if (constructor_unfilled_fields
+ /* Do not warn about initializing with { 0 } or with { }. */
+ && !constructor_zeroinit)
+ {
+ if (!constructor_designated)
+ {
+ if (warning_at (input_location,
OPT_Wmissing_field_initializers,
"missing initializer for field %qD of %qT",
- constructor_unfilled_fields,
- constructor_type))
- inform (DECL_SO
Re: [PATCH v2] Add new warning Wmissing-designated-initializers [PR39589]
Ping https://gcc.gnu.org/pipermail/gcc-patches/2024-September/662590.html
[PING #3][PATCH v2] Add new warning Wmissing-designated-initializers [PR39589]
Hi all, Pinginghttps://gcc.gnu.org/pipermail/gcc-patches/2024-September/662590.html for a review if anyone has a moment. Many thanks, Peter
[PATCH v3] Add new warning Wmissing-designated-initializers [PR39589]
v3 Patch:
* adds documentation
* fixes formatting
* minor code cleanup
Currently the behaviour of Wmissing-field-initializers is inconsistent
between C and C++. The C warning assumes that missing designated
initializers are deliberate, and does not warn. The C++ warning does warn
for missing designated initializers.
This patch changes the behaviour of Wmissing-field-initializers to
universally not warn about missing designated initializers, and adds a new
warning for specifically for missing designated initializers.
NOTE TO MAINTAINERS: This is my first gcc contribution, so I don't have
git write access.
Successfully tested on x86_64-pc-linux-gnu.
PR c/39589
gcc/c-family/ChangeLog:
* c.opt (Wmissing-designated-initializers): New option.
* c.opt.urls: (Wmissing-designated-initializers): New option.
gcc/c/ChangeLog:
* c-typeck.cc (pop_init_level): Generate warning for missing designated
initializers rather than always ignore.
gcc/ChangeLog:
* common.opt.urls: (Wmissing-designated-initializers): New option.
* doc/invoke.texi: (Wmissing-designated-initializers): New option.
gcc/cp/ChangeLog:
* typeck2.cc (process_init_constructor_record): Add check if missing
initializer is designated, warn as appropriate.
gcc/testsuite/ChangeLog:
* g++.dg/diagnostic/base.C: Change flags.
* gcc.dg/20011021-1.c: Fix test, missing designated initializers can
generate a warning now.
* gcc.dg/missing-field-init-1.c: Change flags.
* gcc.dg/pr60784.c: Change flags.
* g++.dg/warn/missing-designated-initializers-1.C: New test.
* g++.dg/warn/missing-designated-initializers-2.C: New test.
* gcc.dg/missing-designated-initializers-1.c: New test.
* gcc.dg/missing-designated-initializers-2.c: New test.
---
gcc/c-family/c.opt| 4 +
gcc/c-family/c.opt.urls | 3 +
gcc/c/c-typeck.cc | 52 -
gcc/common.opt.urls | 2 +-
gcc/cp/typeck2.cc | 100 +-
gcc/doc/invoke.texi | 40 ++-
gcc/testsuite/g++.dg/diagnostic/base.C| 4 +-
.../warn/missing-designated-initializers-1.C | 12 +++
.../warn/missing-designated-initializers-2.C | 12 +++
gcc/testsuite/gcc.dg/20011021-1.c | 17 ++-
.../missing-designated-initializers-1.c | 14 +++
.../missing-designated-initializers-2.c | 14 +++
gcc/testsuite/gcc.dg/missing-field-init-1.c | 2 +-
gcc/testsuite/gcc.dg/pr60784.c| 2 +-
14 files changed, 184 insertions(+), 94 deletions(-)
create mode 100644
gcc/testsuite/g++.dg/warn/missing-designated-initializers-1.C
create mode 100644
gcc/testsuite/g++.dg/warn/missing-designated-initializers-2.C
create mode 100644 gcc/testsuite/gcc.dg/missing-designated-initializers-1.c
create mode 100644 gcc/testsuite/gcc.dg/missing-designated-initializers-2.c
diff --git a/gcc/c-family/c.opt b/gcc/c-family/c.opt
index 15698dc65bb..746adc8aaad 100644
--- a/gcc/c-family/c.opt
+++ b/gcc/c-family/c.opt
@@ -1030,6 +1030,10 @@ Wmissing-field-initializers
C ObjC C++ ObjC++ Var(warn_missing_field_initializers) Warning
EnabledBy(Wextra)
Warn about missing fields in struct initializers.
+Wmissing-designated-initializers
+C ObjC C++ ObjC++ Var(warn_missing_designated_initializers) Warning
EnabledBy(Wextra)
+Warn about missing designated initializers in struct initializers.
+
Wmissing-format-attribute
C ObjC C++ ObjC++ Warning Alias(Wsuggest-attribute=format)
;
diff --git a/gcc/c-family/c.opt.urls b/gcc/c-family/c.opt.urls
index fd7ffd38d53..88772cd113f 100644
--- a/gcc/c-family/c.opt.urls
+++ b/gcc/c-family/c.opt.urls
@@ -553,6 +553,9 @@
UrlSuffix(gcc/Warning-Options.html#index-Wmissing-declarations)
Wmissing-field-initializers
UrlSuffix(gcc/Warning-Options.html#index-Wmissing-field-initializers)
+Wmissing-designated-initializers
+UrlSuffix(gcc/Warning-Options.html#index-Wmissing-designated-initializers)
+
Wmissing-format-attribute
UrlSuffix(gcc/Warning-Options.html#index-Wmissing-format-attribute)
diff --git a/gcc/c/c-typeck.cc b/gcc/c/c-typeck.cc
index dbb688cabaa..37cc95f4a37 100644
--- a/gcc/c/c-typeck.cc
+++ b/gcc/c/c-typeck.cc
@@ -10150,31 +10150,33 @@ pop_init_level (location_t loc, int implicit,
}
/* Warn when some struct elements are implicitly initialized to zero. */
- if (warn_missing_field_initializers
- && constructor_type
- && TREE_CODE (constructor_type) == RECORD_TYPE
- && constructor_unfilled_fields)
-{
- /* Do not warn for flexible array members or zero-length arrays. */
- while (constructor_unfilled_fields
- && (!DECL_SIZE (constructor_unfilled_fields)
- || integer_zerop (DECL_SIZE (constructor_unfilled_fields
- constructor_unfilled_fields = DEC
[PING][PATCH v3] Add new warning Wmissing-designated-initializers [PR39589]
Ping https://gcc.gnu.org/pipermail/gcc-patches/2025-January/672568.html
[PING][PATCH v3] Add new warning Wmissing-designated-initializers [PR39589]
Ping https://gcc.gnu.org/pipermail/gcc-patches/2025-January/672568.html Missed the version 15 freeze with the last ping, I believe the project is open for general development again now?
Re: [PING * 3][PATCH v3] Add new warning Wmissing-designated-initializers [PR39589]
Thanks for the review, much appreciated. Agreed on all those points,
I'll remove it from -Wextra and just leave it as a standalone warning,
and I'll add those tests you suggested.
On 02/06/2025 19:08, Joseph Myers wrote:
On Sun, 1 Jun 2025, Peter Frost wrote:
Ping https://gcc.gnu.org/pipermail/gcc-patches/2025-January/672568.html
This needs various coding style fixes. Lines should be broken before
binary operators such as && or || rather than after, and there should be a
space before '(' in function and macro calls.
I don't think this belongs in -Wextra. For example, it's incompatible
with the use of designated initializers for any structure in standard
headers that has named padding fields - or indeed any structure in
standard headers that has some fields that are implementation extensions
that are irrelevant to the particular application.
I would expect the new tests to include cases of nested structures where
the initializations are done in the form ".a.b.c = 1" and similar.
Likewise, in the array tests, consider
{ [0].a = 1, [1].b = 2, [0].b = 3, [0].c = 4 }
and similar (this is a case where all of .a, .b, .c are initialized in
[0], so there should be no warning for missing initializers in [0] if
those are the only struct members, but .a and .c are missing initializers
in [1]).
[PING * 3][PATCH v3] Add new warning Wmissing-designated-initializers [PR39589]
Ping https://gcc.gnu.org/pipermail/gcc-patches/2025-January/672568.html
