Re: [PATCH v2 09/10] clang: warn when the comma operator is used

> On Tue, Mar 25, 2025 at 11:32:13PM +0000, Johannes Schindelin via GitGitGadget wrote:
> > From: Johannes Schindelin <johannes.schindelin@gmx.de>
> >
> > When compiling Git using `clang`, the `-Wcomma` option can be used to
> > warn about code using the comma operator (because it is typically
> > unintentional and wants to use the semicolon instead).
> >
> > Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
> > ---
> >  config.mak.dev | 4 ++++
> >  1 file changed, 4 insertions(+)
> >
> > diff --git a/config.mak.dev b/config.mak.dev
> > index 0fd8cc4d355..31423638169 100644
> > --- a/config.mak.dev
> > +++ b/config.mak.dev
> > @@ -40,6 +40,10 @@ DEVELOPER_CFLAGS += -Wvla
> >  DEVELOPER_CFLAGS += -Wwrite-strings
> >  DEVELOPER_CFLAGS += -fno-common
> >
> > +ifneq ($(filter clang9,$(COMPILER_FEATURES)),)
> > +DEVELOPER_CFLAGS += -Wcomma
> > +endif
> > +
> >  ifneq ($(filter clang4,$(COMPILER_FEATURES)),)
> >  DEVELOPER_CFLAGS += -Wtautological-constant-out-of-range-compare
> >  endif
>
> Let's squash the below diff into this commit. The loop already makes
> sure that the compiler supports the flag, so there is no need to special
> case Clang.

> diff --git a/meson.build b/meson.build
> index dd231b669b6..a7658d62ea0 100644
> --- a/meson.build
> +++ b/meson.build
> @@ -717,6 +717,7 @@ libgit_dependencies = [ ]
>  # Makefile.
>  if get_option('warning_level') in ['2','3', 'everything'] and compiler.get_argument_syntax() == 'gcc'

>    foreach cflag : [
> +    '-Wcomma',
>      '-Wdeclaration-after-statement',
>      '-Wformat-security',
>      '-Wold-style-definition',
>