https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97618
--- Comment #2 from Brecht Sanders <brechtsanders at users dot sourceforge.net> --- To build mpfr wich fails with: build_mingw\i686-w64-mingw32\libgcc/../../../libgcc/config/libbid/bid128_div.c:1523: undefined reference to `LC4' I figured out that the symbol LC4 is defined in libgcc.a, so I was able to build mpfr by running: make LIBS="-Wl,--as-needed -lgmp -lgcc" It appears that in this case the GCC 11 linker doesn't automatically link with libgcc.