Cross-compiling with OpenSSL for Windows

Question

I'm trying to compile the oauth-utils http://mir.dnsalias.com/oss/oauth/start for Windows from Ubuntu. I have compiled it on Windows before (a few months back), but wanted to try cross-compiling.

I got openssl build using mingw32 ok, and put libssl.a and libcrypto.a in the right place. The linker is now finding the libraries (yay!) but I get the following error:

/usr/lib/gcc/i586-mingw32msvc/4.2.1-sjlj/../../../../i586-mingw32msvc/lib/libcrypto.a(rand_win.o):rand_win.c:(.text+0xaac): undefined reference to `_CreateDCA@16'
/usr/lib/gcc/i586-mingw32msvc/4.2.1-sjlj/../../../../i586-mingw32msvc/lib/libcrypto.a(rand_win.o):rand_win.c:(.text+0xab9): undefined reference to `_CreateCompatibleDC@4'
/usr/lib/gcc/i586-mingw32msvc/4.2.1-sjlj/../../../../i586-mingw32msvc/lib/libcrypto.a(rand_win.o):rand_win.c:(.text+0xacc): undefined reference to `_GetDeviceCaps@8'
/usr/lib/gcc/i586-mingw32msvc/4.2.1-sjlj/../../../../i586-mingw32msvc/lib/libcrypto.a(rand_win.o):rand_win.c:(.text+0xadc): undefined reference to `_GetDeviceCaps@8'
/usr/lib/gcc/i586-mingw32msvc/4.2.1-sjlj/../../../../i586-mingw32msvc/lib/libcrypto.a(rand_win.o):rand_win.c:(.text+0xaf4): undefined reference to `_CreateCompatibleBitmap@12'
/usr/lib/gcc/i586-mingw32msvc/4.2.1-sjlj/../../../../i586-mingw32msvc/lib/libcrypto.a(rand_win.o):rand_win.c:(.text+0xb04): undefined reference to `_SelectObject@8'
/usr/lib/gcc/i586-mingw32msvc/4.2.1-sjlj/../../../../i586-mingw32msvc/lib/libcrypto.a(rand_win.o):rand_win.c:(.text+0xb18): undefined reference to `_GetObjectA@12'
/usr/lib/gcc/i586-mingw32msvc/4.2.1-sjlj/../../../../i586-mingw32msvc/lib/libcrypto.a(rand_win.o):rand_win.c:(.text+0xb81): undefined reference to `_BitBlt@36'
/usr/lib/gcc/i586-mingw32msvc/4.2.1-sjlj/../../../../i586-mingw32msvc/lib/libcrypto.a(rand_win.o):rand_win.c:(.text+0xb8c): undefined reference to `_GetBitmapBits@12'
/usr/lib/gcc/i586-mingw32msvc/4.2.1-sjlj/../../../../i586-mingw32msvc/lib/libcrypto.a(rand_win.o):rand_win.c:(.text+0xbe5): undefined reference to `_SelectObject@8'
/usr/lib/gcc/i586-mingw32msvc/4.2.1-sjlj/../../../../i586-mingw32msvc/lib/libcrypto.a(rand_win.o):rand_win.c:(.text+0xbec): undefined reference to `_DeleteObject@4'
/usr/lib/gcc/i586-mingw32msvc/4.2.1-sjlj/../../../../i586-mingw32msvc/lib/libcrypto.a(rand_win.o):rand_win.c:(.text+0xbf6): undefined reference to `_DeleteDC@4'
/usr/lib/gcc/i586-mingw32msvc/4.2.1-sjlj/../../../../i586-mingw32msvc/lib/libcrypto.a(rand_win.o):rand_win.c:(.text+0xc00): undefined reference to `_DeleteDC@4'

Any ideas what could be causing this?

Thanks.

Answer 1

It seems that if one remove everything between

static void readscreen(void)
{
#if !defined(OPENSSL_SYS_WINCE) && !defined(OPENSSL_SYS_WIN32_CYGWIN)

and

#endif /* !OPENSSL_SYS_WINCE */
}

in rand_win.c, that building works. I'm not 100% sure how safe removing this is.

Answer 2

Are you adding -mwindows to your link command?

Answer 3

Link with Gdi32.lib