`gcc -print-prog-name=cc1plus` -v
`g++ -print-prog-name=cc1plus` -v
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gcc -dumpspecs > specs
When the specs are evaluated, GCC looks for the file <mingw-root>/lib/gcc/mingw32/<gcc-version>/specs
$ gcc -dumpspecs > <mingw-root>/lib/gcc/mingw32/<gcc-version>/specs
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*cpp:
%{posix:-D_POSIX_SOURCE} %{mthreads:-D_MT} -I z:/libx/include
*link_libgcc:
%D -L z:/libx/lib
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*local_prefix:
<mingw-root>/local/
*local_includes:
-I%(local_prefix)include
*local_lib_search:
-L%(local_prefix)lib
*cpp:
%(msvcrt_version) %{posix:-D_POSIX_SOURCE} %{mthreads:-D_MT} %(local_includes)
*link_libgcc:
%D %(local_lib_search)
*cc1plus:
%(local_includes)
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$ C_INCLUDE_PATH=/opt/gdbm-1.8.3/include
$ export C_INCLUDE_PATH
$ CPLUS_INCLUDE_PATH=/opt/gdbm-1.8.3/include
$ export CPLUS_INCLUDE_PATH
$ LIBRARY_PATH=/opt/gdbm-1.8.3/lib
$ export LIBRARY_PATH