Exact inform format escape sequence (GCC 10 or GCC 11)

[Martin Liška]

On 9/10/21 15:05, Basile Starynkevitch wrote:
> Hello all,
> 
> In the Bismon static source code analyzer on https://github.com/bstarynk/bismon/ commit ad8b6270691e
> 
> (funded by http://decoder-project.eu/ ....) which contains some GPLv3+ GCC plugin code under directory gccplugins/
> 
> I am getting when compiling it
> 
> 
> gcc10_metaplugin_BMGCC.cc: In function ‘int plugin_init(plugin_name_args*, plugin_gcc_version*)’:
> gcc10_metaplugin_BMGCC.cc:165:85: warning: unquoted whitespace character ‘\x0a’ in format [-Wformat-diag]
>    165 |     warning(UNKNOWN_LOCATION, "BISMON GCC10 METAPLUGIN: datestamp difference for %s:\n"
> | ^~~
>    166 |      " plugin has %s, GCC had %s; this is risky.",
>        | ~~
> gcc10_metaplugin_BMGCC.cc:169:84: warning: unquoted whitespace character ‘\x0a’ in format [-Wformat-diag]
>    169 |     warning(UNKNOWN_LOCATION, "BISMON GCC10 METAPLUGIN: devphase difference for %s:\n"
> | ^~~
>    170 |      " plugin has %s, GCC had %s; this is risky.",
>        | ~~
> gcc10_metaplugin_BMGCC.cc:174:89: warning: unquoted whitespace character ‘\x0a’ in format [-Wformat-diag]
>    174 |     warning(UNKNOWN_LOCATION, "BISMON GCC10 METAPLUGIN: configuration difference for %s:\n"
> | ^~~
>    175 |      " plugin has %s, GCC had %s; this is risky.",
>        | ~~
> gcc10_metaplugin_BMGCC.cc: In function ‘void parse_plugin_arguments(const char*, plugin_name_args*)’:
> gcc10_metaplugin_BMGCC.cc:405:53: warning: unquoted sequence of 2 consecutive space characters in format [-Wformat-diag]
>    405 |         inform (UNKNOWN_LOCATION, "Bismon plugin %qs (%s:%d) will handle GCC include-file events with prefix %qs",
>        |                                                     ^~
> 

Hello.

The warning -Wformat-diag is internal GCC warning that hasn't been documented. I'm CC'ing the warning author.

> 
> 
> Where can I read the complete specification of % escape sequences for inform?

You can read it just in source code if I'm correct, that's the only option you have:
gcc/c-family/c-format.c:3031.

Martin

> 
> 
> Thanks
> 
> 
> 
> 
> Basile Starynkevitch                  <basile@starynkevitch.net>
> (only mine opinions / les opinions sont miennes uniquement)
> 92340 Bourg-la-Reine, France
> web page: starynkevitch.net/Basile/
>