[Bug] lib: GCC format-overflow in G_recursive_remove

[wenzeslaus]

Describe the bug

Compilation of G_recursive_remove complains about "'%s' directive writing up to 255 bytes into a region of size between 1 and 4095" with -Wformat-overflow for sprintf(path2, "%s/%s", path, dp->d_name);.

To reproduce

Run compilation with -Wformat-overflow= (using GCC v13?) or in the nix develop environment.

Expected behavior

No errors or warnings, possibly warnings treated as errors.

Screenshots

gcc  -g -O2  -fPIC  -I/.../grass/dist.x86_64-pc-linux-gnu/include -I/.../grass/dist.x86_64-pc-linux-gnu/include    -DGRASS_VERSION_DATE=\"'2024'\" -DPACKAGE=\""grasslibs"\"        -I/.../grass/dist.x86_64-pc-linux-gnu/include -I/.../grass/dist.x86_64-pc-linux-gnu/include -DRELDIR=\"lib/gis\" -o OBJ.x86_64-pc-linux-gnu/set_window.o -c set_window.c
gcc  -g -O2  -fPIC  -I/.../grass/dist.x86_64-pc-linux-gnu/include -I/.../grass/dist.x86_64-pc-linux-gnu/include    -DGRASS_VERSION_DATE=\"'2024'\" -DPACKAGE=\""grasslibs"\"        -I/.../grass/dist.x86_64-pc-linux-gnu/include -I/.../grass/dist.x86_64-pc-linux-gnu/include -DRELDIR=\"lib/gis\" -o OBJ.x86_64-pc-linux-gnu/short_way.o -c short_way.c
remove.c: In function 'G_recursive_remove':
remove.c:132:28: warning: '%s' directive writing up to 255 bytes into a region of size between 1 and 4095 [-Wformat-overflow=]
  132 |         sprintf(path2, "%s/%s", path, dp->d_name);
      |                            ^~
In file included from /nix/store/wlavaybjbzgllhq11lib6qgr7rm8imgp-glibc-2.39-52-dev/include/stdio.h:980,
                 from remove.c:15:
In function 'sprintf',
    inlined from 'G_recursive_remove' at remove.c:132:9:
/nix/store/wlavaybjbzgllhq11lib6qgr7rm8imgp-glibc-2.39-52-dev/include/bits/stdio2.h:30:10: note: '__builtin___sprintf_chk' output between 2 and 4351 bytes into a destination of size 4096
   30 |   return __builtin___sprintf_chk (__s, __USE_FORTIFY_LEVEL - 1,
      |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   31 |                                   __glibc_objsize (__s), __fmt,
      |                                   ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   32 |                                   __va_arg_pack ());
      |                                   ~~~~~~~~~~~~~~~~~
gcc  -g -O2  -fPIC  -I/.../grass/dist.x86_64-pc-linux-gnu/include -I/.../grass/dist.x86_64-pc-linux-gnu/include    -DGRASS_VERSION_DATE=\"'2024'\" -DPACKAGE=\""grasslibs"\"        -I/.../grass/dist.x86_64-pc-linux-gnu/include -I/.../grass/dist.x86_64-pc-linux-gnu/include -DRELDIR=\"lib/gis\" -o OBJ.x86_64-pc-linux-gnu/sleep.o -c sleep.c

System description

• Our nix develop environment on Ubuntu 22.04.
• gcc (GCC) 13.3.0 (2023)
• GRASS GIS 8.5.0dev 573d54a

Additional context

• [Bug] GCC nonnull and format-overflow in r.fill.stats #4472