Hi!
I've reworded the patch to remove any references to obsoletion, but kept
the diagnostic in -Wextra, as I don't expect this to break any old code.
I didn't do any regression testing this time, as I didn't change
anything meaningfully. I just made sure it still builds.
See the range-diff below.
Have a lovely day!
Alex
Alejandro Colomar (1):
c, objc: Add -Wmultiple-parameter-fwd-decl-lists
gcc/c-family/c.opt | 4 ++++
gcc/c/c-decl.cc | 16 +++++++++-------
gcc/doc/extend.texi | 2 +-
gcc/doc/invoke.texi | 12 +++++++++++-
.../gcc.dg/Wmultiple-parameter-fwd-decl-lists.c | 6 ++++++
5 files changed, 31 insertions(+), 9 deletions(-)
create mode 100644 gcc/testsuite/gcc.dg/Wmultiple-parameter-fwd-decl-lists.c
Range-diff against v3:
1: 83fbe0d41f3 ! 1: 3370790e940 c, objc: Deprecate more than one list of
forward declarations of parameters
@@ Metadata
Author: Alejandro Colomar <[email protected]>
## Commit message ##
- c, objc: Deprecate more than one list of forward declarations of
parameters
+ c, objc: Add -Wmultiple-parameter-fwd-decl-lists
Warn about this:
void f(int x; int x; int x);
- This would allow eventually adding another semicolon in function
- prototypes to separate a different feature.
+ Add a new diagnostic, -Wmultiple-parameter-fwd-decl-lists, which
+ diagnoses uses of this obsolescent syntax.
- So, make multiple lists of forward declarations of parameters
- obsolescent, and produce a new diagnostic,
- -Wmultiple-parameter-fwd-decl-lists, which diagnoses uses of this
- obsolescent syntax.
+ Add this diagnostic in -Wextra.
- Forward declarations of parameters are a rarely used feature, AFAIK,
- (and having more than one would be even rarer) so this shouldn't be
- problematic in -Wextra. Eventually, we may want to move this into
- a default diagnostic, and later an error.
+ Forward declarations of parameters are very rarely used. And functions
+ that need two forward declaractions of parameters are also quite rare.
+ This combination results in this code almost not existing in any code
+ base, which makes adding this to -Wextra okay. FWIW, I've tried
finding
+ such code using a code search engine, and didn't find any cases (but
the
+ regex for that isn't easy to writei, so I wouldn't trust it).
gcc/c-family/ChangeLog:
@@ gcc/c/c-decl.cc: mark_forward_parm_decls (void)
- }
+ if (current_scope->had_forward_parm_decls)
+ warning_at (input_location, OPT_Wmultiple_parameter_fwd_decl_lists,
-+ "more than one list of forward declarations of parameters are
an obsolescent feature");
++ "more than one list of forward declarations of parameters");
+ if (pedantic && !current_scope->had_forward_parm_decls)
+ pedwarn (input_location, OPT_Wpedantic,
+ "ISO C forbids forward parameter declarations");
@@ gcc/doc/invoke.texi: is not considered an old-style definition in C23
mode, beca
+@opindex Wno-multiple-parameter-fwd-decl-lists
+@item -Wmultiple-parameter-fwd-decl-lists @r{(C and Objective-C only)}
+Warn if more than one list of forward declarations of parameters
-+appears in a function prototype,
-+which is an obsolescent feature.
++appears in a function prototype.
+This warning is also enabled by @option{-Wextra}.
+
@opindex Wdeprecated-non-prototype
--
2.50.1
