Continuing from here, I am trying to build 64-bit GSL using GCC in Cygwin.
The call to ./configure (CC=x86_64-w64-mingw32-gcc CFLAGS=-m64 ./configure) goes through fine, but the call to make install results, after a whole load of folders are successfully processed, in
./.libs/libgslsiman.a: could not read symbols: Archive has no index; run ranlib to add one
collect2: ld returned 1 exit status
Makefile:326: recipe for target `siman_tsp.exe' failed
The full call that caused this was
Making all in siman make2: Entering directory `/cygdrive/f/programming/c/libraries/gslCompiled/gsl-1.15/siman'
/bin/sh ../libtool --tag=CC --mode=link x86_64-w64-mingw32-gcc -m64 -o siman_tsp.exe siman_tsp.o libgslsiman.la ../rng/libgslrng.la ../ieee-utils/libgslieeeutils.la ../err/libgslerr.la ../sys/libgslsys.la ../utils/libutils.la -lm
libtool: link: x86_64-w64-mingw32-gcc -m64 -o .libs/siman_tsp.exe siman_tsp.o ./.libs/libgslsiman.a ../rng/.libs/libgslrng.a ../ieee-utils/.libs/libgslieeeutils.a ../err/.libs/libgslerr.a ../sys/.libs/libgslsys.a ../utils/.libs/libutils.a
Following advice here, I decided to run a ranlib in the ./siman/.libs directory on the libgslsiman.a file. Since that didn't work, I also tried to pack it myself using a call to ar -t libgslsiman.a.
However, this results in an identical error.
You manually forced use of the cross compiler. However, the rest of the build toolchain will still default to the 32-bit Cygwin versions instead of the 64-bit MinGW ones.
Instead of setting CC=..., pass --host x86_64-w64-mingw32 to ./configure to specify the host environment (ie where the library is going to be used).