Fixed in commit 2cb4ca6 by remove asla-lib from inputs. SDL_mixer do a testing for libmikmod using libmikmod-config. libmikmod-config.in has: --libs) echo -L@libdir@ -lmikmod @LIBRARY_LIB@
When built with alsa driver support, @LIBRARY_LIB@ become "-lm -lasound", require alsa-lib presented to get the test success. But in fact the use of libmikmod library don't depends on the drivers (alsa), and the libmikmod.pc file doesn't have them in Libs (and Libs.private). So I think it's a bug where @LIBRARY_LIB@ contains '-lasound'. Instead of dropping @LIBRARY_LIB@ from libmikmod-config.in, I notice that the only user of libmikmod is sdl-mixer, which use it's own audio output drivers. So I'm temped to remove alsa-lib from libmikmod (the libx11 is unused IIRC).