After I have read several forum posts to my problem which not helped me at all, I ask you for help.
I am trying to create a .dll with GNU compiler on Windows. This .dll needs a library, we call it mylib for now, to work. So i create a static library mylib.a with:
ar rcs mylib.a file1.o file2.o file3.o file4.o
I created the .o files individually with
g++ -c file1.cpp.
Now to create the .dll and link mylib.a I enter the following command:
g++ -shared -o mydll.dll Dynamicfunc.cpp -l:mylib.a
where Dynamicfunc.cpp contains the implementation of the .dll.
When executing this command, the following error message appears:
C:/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/13.2.0/../../../x86_64-w64-mingw32/bin/ld.exe: cannot find -l:mylib.a: No such file or directory
collect2.exe: error: ld returned 1 exit status
In most posts on this topic, the solution to the problem was to add the prefix "lib". So in my case -l:libmylib.a which unfortunately did not work either. Furthermore the mylib.a file is in the same directory as Dynamicfunc.cpp which makes using -L not necessary but even with -L:C:……\src, ld.exe does not find the specified mylib.a file.
If i turn all the object files (file1.o file2.o…) into a .lib instead of a .a library it also doesn´t work.
Furthermore I have tried to create mylib.a without
ar rcs libout.a ...
but with
g++ -static -o mylib.a file1.o file2.o ...
also without success.
I would really appreciate any suggestions.
g++ -v:
Using built-in specs.
COLLECT_GCC=g++
COLLECT_LTO_WRAPPER=C:/mingw64/bin/../libexec/gcc/x86_64-w64-mingw32/13.2.0/lto-wrapper.exe
OFFLOAD_TARGET_NAMES=nvptx-none
Target: x86_64-w64-mingw32
Configured with: ../configure --prefix=/R/winlibs64ucrt_stage/inst_gcc-13.2.0/share/gcc --build=x86_64-w64-mingw32 --host=x86_64-w64-mingw32 --enable-offload-targets=nvptx-none --with-pkgversion='MinGW-W64 x86_64-ucrt-posix-seh, built by Brecht Sanders'
--with-tune=generic --enable-checking=release --enable-threads=posix --disable-sjlj-exceptions --disable-libunwind-exceptions --disable-serial-configure --disable-bootstrap --enable-host-shared --enable-plugin --disable-default-ssp --disable-rpath --disable-libstdcxx-debug --disable-version-specific-runtime-libs
--with-stabs --disable-symvers --enable-languages=c,c++,fortran,lto,objc,obj-c++ --disable-gold --disable-nls --disable-stage1-checking --disable-win32-registry --disable-multilib --enable-ld --enable-libquadmath --enable-libada --enable-libssp --enable-libstdcxx --enable-lto --enable-fully-dynamic-string --enable-libgomp
--enable-graphite --enable-mingw-wildcard --enable-libstdcxx-time --enable-libstdcxx-pch --with-mpc=/d/Prog/winlibs64ucrt_stage/custombuilt --with-mpfr=/d/Prog/winlibs64ucrt_stage/custombuilt --with-gmp=/d/Prog/winlibs64ucrt_stage/custombuilt --with-isl=/d/Prog/winlibs64ucrt_stage/custombuilt
--disable-libstdcxx-backtrace --enable-install-libiberty --enable-__cxa_atexit --without-included-gettext --with-diagnostics-color=auto --enable-clocale=generic --with-libiconv --with-system-zlib
--with-build-sysroot=/R/winlibs64ucrt_stage/gcc-13.2.0/build_mingw/mingw-w64 CFLAGS='-I/d/Prog/winlibs64ucrt_stage/custombuilt/include/libdl-win32 -Wno-int-conversion -march=nocona -msahf -mtune=generic -O2' CXXFLAGS='-Wno-int-conversion -march=nocona -msahf -mtune=generic -O2' LDFLAGS='-pthread -Wl,--no-insert-timestamp -Wl,--dynamicbase -Wl,--high-entropy-va -Wl,--nxcompat -Wl,--tsaware'
Thread model: posix
Supported LTO compression algorithms: zlib zstd
gcc version 13.2.0 (MinGW-W64 x86_64-ucrt-posix-seh, built by Brecht Sanders)
>Solution :
-l:mylib.a searches the library search path for a file named mylib.a. The current working directory is not in the library search path by default. You can add it there:
gcc ... -L. -l:mylib.a
or just use the file name directly with no -l flag:
gcc ... mylib.a
If you are creating a DLL, you might need another couple of flags:
gcc -shared ... -Wl,-whole-archive mylib.a -Wl,-no-whole-archive
g++ -static -o mylib.a ... won’t work. Use ar to create a static library.