Re: test-sprintf-posix and test-snprintf-posix test failures

[Bruno Haible]

Hi Collin,

welcome to the daily business of Gnulib test failures and workarounds!

> backtrace from test-sprintf-posix:
> ======================================
> #4  0x00000000004090cd in test_function (my_sprintf=<optimized out>) at 
> /home/collin/.local/src/gnulib/testdir/gltests/test-sprintf-posix.h:3174
>         retval = 5
>         result = "a\000z 33\000    
> 33\000cwlthcnggomhnqgbsynfxjndfoctldsdihygdqrghvtdxanjnzstbpklsewtvbncwuvbkwmfcbdjrboewqnmnqubkvhvldwqnkjjlotyfnwgsesgwmdwpjeaxutsssuwzcglqwdksajtdozlxkxkyncsiypgxpibunhbwrmieaxurpnljihggggghi"...
>         buf = "12345\000EF"
>         L_xyz = L"xyz"
> ======================================
> 
> The reval is incorrect here:
> 
>   { /* NUL character.  */
>     int retval =
>       my_sprintf (result, "a%lcz %d", (wint_t) L'\0', 33, 44, 55);
>     /* ISO C had this wrong for decades.  ISO C 23 now corrects it, through
>        this wording:
>        "If an l length modifier is present, the wint_t argument is converted
>         as if by a call to the wcrtomb function with a pointer to storage of
>         at least MB_CUR_MAX bytes, the wint_t argument converted to wchar_t,
>         and an initial shift state."  */
>     ASSERT (memcmp (result, "a\0z 33\0", 6 + 1) == 0);
>     ASSERT (retval == 6);
>   }

Does the test failure persist when you disable the other tests from the
same source file (with #if 0 / #endif)?

Does the test failure persist when the tests are compiled with "-ggdb"
instead of "-g -O2"? (Change CFLAGS in gltests/Makefile.)

Does the test program use rpl_sprintf defined by Gnulib, or does it use
sprintf from glibc directly? (Use 'nm test-sprintf | grep printf'.) In
the first case, does the test failure persist when the Gnulib replacement
code is compiled with "-ggdb" instead of "-g -O2"? (Change CFLAGS in
gllib/Makefile.)

Bruno