Unresolved externals with statically built ffmpeg on Windows

Question

I built ffmpeg 1.2.1 as a static lib - x64, debug. And I tried to open one of my older projects that links against it. After modifying some changed APIs and similar in my source, it compiled fine, but I have major problems with linking.

EDITED: the complete latest build output:

1>libavformat.a(mov.o) : error LNK2019: unresolved external symbol __imp__gmtime64 referenced in function mov_read_mvhd
1>libavutil.a(parseutils.o) : error LNK2001: unresolved external symbol __imp__gmtime64
1>libavformat.a(os_support.o) : error LNK2019: unresolved external symbol __imp__wsopen referenced in function ff_win32_open
1>libavcodec.a(pthread.o) : error LNK2019: unresolved external symbol __imp__beginthreadex referenced in function ff_thread_init
1>libavcodec.a(frame_thread_encoder.o) : error LNK2001: unresolved external symbol __imp__beginthreadex
1>libavutil.a(parseutils.o) : error LNK2019: unresolved external symbol __imp__localtime64 referenced in function av_parse_time
1>libavutil.a(parseutils.o) : error LNK2019: unresolved external symbol __imp__time64 referenced in function av_parse_time
1>libavutil.a(parseutils.o) : error LNK2019: unresolved external symbol __imp__mktime64 referenced in function av_parse_time
1>libmingwex.a(lib64_libmingwex_a-mingw_output_format.o) : error LNK2019: unresolved external symbol __mingw_get_msvcrt_handle referenced in function __mingw_set_output_format
1>libmingwex.a(lib64_libmingwex_a-mingw_get_codepage.o) : error LNK2001: unresolved external symbol __mingw_get_msvcrt_handle

What am I doing wrong?
What am I missing here?
Does ffmpeg even work today on Windows platform as a static lib, or it becomes less functional on Windows with each new version?

Please tell your configuration setting when build it. – Wildan Muhlis Jul 11 '13 at 15:54 — Wildan Muhlis, Jul 11 '13 at 15:54
@Wildan, the problem is in MinGW. – user1764961 Jul 15 '13 at 13:24 — user1764961, Jul 15 '13 at 13:24

score 0 · Answer 1 · answered Jul 07 '13 at 14:06

First 8 errors could be solved by manually inserting

#define _CRTIMP

in some files. This will prevent incorrect use of declspec(__dllimport). We are building a static lib, not a DLL, so it shouldn't be there. I also tried using --extra-cflags='-D_CRTIMP' while running configure before building ffmpeg, but it brakes the build totally. So, manual way is the only way.

The last 2 errors are total bitch:

libmingwex.a(lib64_libmingwex_a-mingw_output_format.o) : error LNK2019: unresolved external symbol __mingw_get_msvcrt_handle referenced in function __mingw_set_output_format
1>libmingwex.a(lib64_libmingwex_a-mingw_get_codepage.o) : error LNK2001: unresolved external symbol __mingw_get_msvcrt_handle

I found these symbols in libmingw32.a (if I remember correctly). But, when I link it, I have conflicts with LIBCMTD.lib. Removing the LIBCMTD.lib creates tons of unresolved externals.

So, I would say that today we are not able to build ffmpeg as static x64 lib on Windows. It was in a way expected, because each new version was less Windows friendly.

Unresolved externals with statically built ffmpeg on Windows

1 Answers1