Re: "localename" functions suggest pure/const attribute

[Assaf Gordon]

Follow-up:

On 07/09/2014 08:29 PM, Assaf Gordon wrote:
> Relating to a coreutil patch I previously sent, I'm using gnulib's "localename" 
> module.
> Compiling it triggers two warnings (and errors with -Werror) about functions 
> being candidates for pure/const attributes.
> I couldn't trigger it directly with gnulib, but it's reproducible with 
> "coreutils":

To reproduce with gnulib, try the following:
====
# start tests as usual - they will succeed (or fail, but unrelated to this 
issue)
$ ./gnulib-tool --test localename

# manually go into the test directory, and re-compile with the warning flags
$ cd testdir*/build
$ find -name "*.o" -delete
$ make CFLAGS="-O1 -g -Werror -Wsuggest-attribute=const 
-Wsuggest-attribute=pure"

make  all-recursive
make[1]: Entering directory `/home/gordon/projects/gnulib/testdir30793/build'
Making all in gllib
make[2]: Entering directory 
`/home/gordon/projects/gnulib/testdir30793/build/gllib'
make  all-recursive
make[3]: Entering directory 
`/home/gordon/projects/gnulib/testdir30793/build/gllib'
make[4]: Entering directory 
`/home/gordon/projects/gnulib/testdir30793/build/gllib'
depbase=`echo localename.o | sed 's|[^/]*$|.deps/&|;s|\.o$||'`;\
        gcc -Wall -DHAVE_CONFIG_H -I. -I../../gllib -I..  -DGNULIB_STRICT_CHECKING=1   
-O1 -g -Werror -Wsuggest-attribute=const -Wsuggest-attribute=pure -MT localename.o -MD 
-MP -MF $depbase.Tpo -c -o localename.o ../../gllib/localename.c &&\
        mv -f $depbase.Tpo $depbase.Po
../../gllib/localename.c: In function ‘string_hash’:
../../gllib/localename.c:2519:1: error: function might be candidate for 
attribute ‘pure’ if it is known to return normally 
[-Werror=suggest-attribute=pure]
 string_hash (const void *x)
 ^
cc1: all warnings being treated as errors
make[4]: *** [localename.o] Error 1
make[4]: Leaving directory 
`/home/gordon/projects/gnulib/testdir30793/build/gllib'
make[3]: *** [all-recursive] Error 1
make[3]: Leaving directory 
`/home/gordon/projects/gnulib/testdir30793/build/gllib'
make[2]: *** [all] Error 2
make[2]: Leaving directory 
`/home/gordon/projects/gnulib/testdir30793/build/gllib'
make[1]: *** [all-recursive] Error 1
make[1]: Leaving directory `/home/gordon/projects/gnulib/testdir30793/build'
make: *** [all] Error 2

=====

(Enabling the warnings with "gnulib-tool" prevents the test framework from 
bootstrapping in the first place).

Regards,
 -gordon