wasm-ld: error: archive has no index; run ranlib to add one

[Beuc]

Hi,

I'm getting these with tot-upstream while compiling ffmpeg (script)

make: ['make']
LD	libswresample/libswresample.so.2
emcc:WARNING: ignoring unsupported linker flag: `-soname`
emcc:WARNING: ignoring unsupported linker flag: `libswresample.so.2`
emcc:WARNING: ignoring unsupported linker flag: `-z`
emcc:WARNING: ignoring unsupported linker flag: `noexecstack`
wasm-ld: error: libavutil/libavutil.a: archive has no index; run ranlib to add one
wasm-ld: error: libavutil/libavutil.a: archive has no index; run ranlib to add one
shared:ERROR: '/home/me/workdir/emtests/renpyweb-asyncify/emsdk/upstream/bin/wasm-ld -o libswresample/libswresample.so.2 --allow-undefined --import-memory --import-table --lto-O0 libswresample/audioconvert.o libswresample/dither.o libswresample/log2_tab.o libswresample/options.o libswresample/rematrix.o libswresample/resample.o libswresample/resample_dsp.o libswresample/swresample.o libswresample/swresample_frame.o libavutil/libavutil.a libavutil/libavutil.a -mllvm -combiner-global-alias-analysis=false -mllvm -enable-emscripten-sjlj -mllvm -disable-lsr --export __wasm_call_ctors --export __data_end --export main --export malloc --export free --export setThrew --export __errno_location --export fflush -z stack-size=5242880 --initial-memory=16777216 --no-entry --max-memory=16777216 --global-base=1024 --relocatable' failed (1)

This breaks the build process, and this didn't happen with 'fastcomp'.

(I see this error referenced in #8995 but it looks like that bug was about something else, hence the separate bug.)

[sbc100]

Its because emar (or llvm-ar) was not used to create the archive. Your system ar does't know about wasm object files so can't create the index.

Setting AR=emar in the same way that you might set CC=emcc is the correct solution.

Feel free to reopen if that doesn't work for you.

[jakogut]

Another option is to configure with --ar=emar.

[Beuc]

Thanks for the info, indeed ffmpeg doesn't honor the AR environment variable (emconfigure).
Specifying emranlib was also needed.

@sbc100 note that I can't reopen bugs unless I was the one closing them AFAIU!

[kripken]

note that I can't reopen bugs unless I was the one closing them AFAIU!

Sorry, yeah, I'm not sure why github is like that. But if you ask in a comment to reopen an issue we'll reopen it!

[sbc100]

Ha, I had no idea github worked like that either! Maybe its a setting we have? I will be more conservative in closing issues from now on.