[Debian-med-packaging] Bug#1098113: wtdbg2: ftbfs with GCC-15

[Matthias Klose]

Package: src:wtdbg2
Version: 2.5-10
Severity: important
Tags: sid forky
User: debian-gcc at lists.debian.org
Usertags: ftbfs-gcc-15

[This bug is NOT targeted to the upcoming trixie release]

Please keep this issue open in the bug tracker for the package it
was filed for.  If a fix in another package is required, please
file a bug for the other package (or clone), and add a block in this
package. Please keep the issue open until the package can be built in
a follow-up test rebuild.

The package fails to build in a test rebuild on at least amd64 with
gcc-15/g++-15, but succeeds to build with gcc-14/g++-14. The
severity of this report will be raised before the forky release.

The full build log can be found at:
http://qa-logs.debian.net/2025/02/16/amd64exp/wtdbg2_2.5-10_unstable_gccexp.log.gz
The last lines of the build log are at the end of this report.

To build with GCC 15, either set CC=gcc-15 CXX=g++-15 explicitly,
or install the gcc, g++, gfortran, ... packages from experimental.

  apt-get -t=experimental install g++ 

GCC 15 now defaults to the C23/C++23 standards, exposing many FTBFS.
Other Common build failures are new warnings resulting in build failures
with -Werror turned on, or new/dropped symbols in Debian symbols files.
For other C/C++ related build failures see the porting guide at
http://gcc.gnu.org/gcc-15/porting_to.html

[...]
mem_share.h:519:33: warning: ignoring return value of ‘fscanf’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
  519 |                                 fscanf(fp, "%llu", &buffered);
      |                                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
mem_share.h:521:33: warning: ignoring return value of ‘fscanf’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
  521 |                                 fscanf(fp, "%llu", &cached);
      |                                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~
mem_share.h: In function ‘get_linux_proc_info’:
mem_share.h:560:9: warning: ignoring return value of ‘fscanf’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
  560 |         fscanf(fp, "%lu%lu", &tmp, &tmp2);
      |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
mem_share.h:568:9: warning: ignoring return value of ‘fscanf’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
  568 |         fscanf(fp, "%lu%lu", &tmp, &tmp2);
      |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
mem_share.h: In function ‘mem_read_obj_file’:
mem_share.h:1222:9: warning: ignoring return value of ‘fread’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
 1222 |         fread(size, sizeof(size_t), 1, file);
      |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
mem_share.h:1223:9: warning: ignoring return value of ‘fread’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
 1223 |         fread(mem_type, sizeof(size_t), 1, file);
      |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
mem_share.h:1224:9: warning: ignoring return value of ‘fread’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
 1224 |         fread(cnt, sizeof(size_t), 1, file);
      |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
mem_share.h:1225:9: warning: ignoring return value of ‘fread’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
 1225 |         fread(aux_data, sizeof(size_t), 1, file);
      |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
mem_share.h: In function ‘mem_load_obj’:
mem_share.h:919:42: warning: this statement may fall through [-Wimplicit-fallthrough=]
  919 |                                 for(m=0;m<cnt;m++){
      |                                         ~^~~~
mem_share.h:925:25: note: here
  925 |                         default: return addr;
      |                         ^~~~~~~
mem_share.h: In function ‘mem_size_obj’:
mem_share.h:793:30: warning: this statement may fall through [-Wimplicit-fallthrough=]
  793 |                 case 3: size += mem_size_round(sizeof(void*) * cnt);
      |                              ^~
mem_share.h:794:17: note: here
  794 |                 case 2:
      |                 ^~~~
In file included from kbm.h:26:
filereader.h: In function ‘file_src_thread_func’:
filereader.h:157:43: warning: this statement may fall through [-Wimplicit-fallthrough=]
  157 |                                         if(_file == NULL){
      |                                           ^
filereader.h:162:33: note: here
  162 |                                 case FILEREADER_ATTR_PROC:
      |                                 ^~~~
filereader.h:163:43: warning: this statement may fall through [-Wimplicit-fallthrough=]
  163 |                                         if(_file == NULL){
      |                                           ^
filereader.h:168:33: note: here
  168 |                                 case FILEREADER_ATTR_USER:
      |                                 ^~~~
filereader.h:169:43: warning: this statement may fall through [-Wimplicit-fallthrough=]
  169 |                                         if(_file == NULL){
      |                                           ^
filereader.h:174:33: note: here
  174 |                                 default:
      |                                 ^~~~~~~
make[2]: *** [Makefile:37: wtpoa-cns-sse2] Error 1
make[2]: *** Waiting for unfinished jobs....
make[2]: *** [Makefile:28: kbm2-sse2] Error 1
make[2]: *** [Makefile:31: wtdbg2-sse2] Error 1
make[2]: Leaving directory '/build/reproducible-path/wtdbg2-2.5'
dh_auto_build: error: make -j8 "INSTALL=install --strip-program=true" SFX=-sse2 returned exit code 2
make[1]: *** [debian/rules:28: override_dh_auto_build] Error 25
make[1]: Leaving directory '/build/reproducible-path/wtdbg2-2.5'
make: *** [debian/rules:22: binary] Error 2
dpkg-buildpackage: error: debian/rules binary subprocess returned exit status 2