Hannes Domani wrote: > Compiling fails like this: > > $ gcc -o conftest.exe -g -O2 -I/gdb/gdb-libs64/include conftest.c > -L/gdb/gdb-libs64/lib -lpoke -lgc > c:/msys64/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/11.2.0/../../../../x86_64-w64-mingw32/bin/ld.exe: > C:/gdb/gdb-libs64/lib/libpoke.a(libgnu_la-close.o): in function `rpl_close': > C:\src\repos\poke\poke.git-build\gl-libpoke/../../../poke.git/gl-libpoke/close.c:71: > undefined reference to `_gl_unregister_fd' > ... > > All of these function calls are inside an #if REPLACE_FCHDIR block, but > fchdir.c itself was not compiled into libpoke.a.
The technical explanation of the cause is: poke uses some gnulib modules which make uses of the Unix idiom that it is possible to open() a directory and get a file descriptor. This idiom requires extra Gnulib code, conditionalized by REPLACE_FCHDIR. It could be that poke (the program) opens a directory descriptor in this way and libpoke needs to close it; that's the reason for the _gl_unregister_fd in gl-libpoke/close.c. Linking gdb (which does not use the Gnulib 'fchdir' module) with libpoke thus produces this undefined symbol. The easiest workaround/fix is probably that libpoke imports the Gnulib 'fchdir' module. Bruno
