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llvmgmpemscripten

Can't get GMP lib compiling with Emscripten

I've tried the instructions here with the latest version of Emscripten: https://github.com/kripken/gmp.js/blob/master/README.markdown

The .a file seems to be correctly created. I then try to compile against that library (in debug mode), and that seems to work:

emcc invocation:  /home/marcosscriven/sources/emscripten/emcc -O0 --closure 0 test.c .libs/libgmp.a -o complete.js 
(Emscripten: Running sanity checks)
emcc: compiling to bitcode
emcc: compiling source file:  test.c
emcc running: /usr/local/bin/clang -m32 -U__i386__ -U__x86_64__ -U__i386 -U__x86_64 -Ui386 -Ux86_64 -U__SSE__ -U__SSE2__ -U__MMX__ -UX87_DOUBLE_ROUNDING -UHAVE_GCC_ASM_FOR_X87 -DEMSCRIPTEN -U__STRICT_ANSI__ -U__CYGWIN__ -D__STDC__ -Xclang -triple=i386-pc-linux-gnu -D__IEEE_LITTLE_ENDIAN -fno-math-errno -fno-ms-compatibility -nostdinc -Xclang -nobuiltininc -Xclang -nostdsysteminc -Xclang -isystem/home/marcosscriven/sources/emscripten/system/local/include -Xclang -isystem/home/marcosscriven/sources/emscripten/system/include -Xclang -isystem/home/marcosscriven/sources/emscripten/system/include/emscripten -Xclang -isystem/home/marcosscriven/sources/emscripten/system/include/bsd -Xclang -isystem/home/marcosscriven/sources/emscripten/system/include/libc -Xclang -isystem/home/marcosscriven/sources/emscripten/system/include/libcxx -Xclang -isystem/home/marcosscriven/sources/emscripten/system/lib/libcxxabi/include -Xclang -isystem/home/marcosscriven/sources/emscripten/system/include/gfx -Xclang -isystem/home/marcosscriven/sources/emscripten/system/include/net -Xclang -isystem/home/marcosscriven/sources/emscripten/system/include/SDL -U__APPLE__ -U__linux__ -D_LIBCPP_HAS_NO_DELETED_FUNCTIONS -emit-llvm -c test.c -o /tmp/tmp_pOV54/test_0.o
emcc: copying library file:  .libs/libgmp.a
emcc: will generate JavaScript
emcc: considering including libcxx: we need set([]) and have set([])
emcc: considering including libcxxabi: we need set([]) and have set([])
emcc: considering including libc: we need set(['realloc', 'malloc', 'memcpy', 'free']) and have set([])
emcc: including libc
emcc: linking:  ['/tmp/tmp_pOV54/test_0.o', '/tmp/tmp_pOV54/libgmp_1.a', '/home/marcosscriven/.emscripten_cache/libc.bc']
emcc: llvm-linking: ['/tmp/tmp_pOV54/test_0.o', '/home/marcosscriven/.emscripten_cache/libc.bc']
emcc: saving intermediate processing steps to /tmp/emscripten_temp
emcc: LLVM opts: ['-internalize', '-internalize-public-api-list=main', '-globaldce']
emcc:    step took 0.01 seconds
emcc:    step took 0.00 seconds
emcc: LLVM => JS
emscript: ll=>js
  emscript: scan took 0.000277042388916 seconds
  emscript: split took 0.000169038772583 seconds
  emscript: phase 1 took 0.173984050751 seconds
  emscript: phase 2 working on 1 chunks  (intended chunk size: 1.00 MB, meta: 0.00 MB, forwarded: 0.01 MB, total: 0.01 MB)
  emscript: phase 2 took 0.206316947937 seconds
  emscript: phase 2b took 0.000115871429443 seconds
  emscript: phase 2c took 0.00135588645935 seconds
  emscript: phase 3 took 0.170216083527 seconds
emcc:    step took 0.60 seconds
emcc: total time: 1.62 seconds

However, when I try to run the generated Javascript, I get this error:

marcosscriven@ubuntu-laptop:~/sources/gmp-5.0.2$ node complete.js 

/home/marcosscriven/sources/gmp-5.0.2/complete.js:2452
      ___gmpz_init(((5242892)|0));
      ^
TypeError: undefined is not a function
    at _pidigits (/home/marcosscriven/sources/gmp-5.0.2/complete.js:2452:7)
    at Object._main (/home/marcosscriven/sources/gmp-5.0.2/complete.js:2429:7)
    at Object.callMain (/home/marcosscriven/sources/gmp-5.0.2/complete.js:2644:24)
    at doRun (/home/marcosscriven/sources/gmp-5.0.2/complete.js:2679:20)
    at run (/home/marcosscriven/sources/gmp-5.0.2/complete.js:2703:12)
    at Object.<anonymous> (/home/marcosscriven/sources/gmp-5.0.2/complete.js:2725:13)
    at Module._compile (module.js:449:26)
    at Object.Module._extensions..js (module.js:467:10)
    at Module.load (module.js:356:32)
    at Function.Module._load (module.js:312:12)

Alon (the creator of Emscripten), over on the Emscripten Google Group, says that means the function is not there, and to check with llvm-vm, which it does appear to be:

marcosscriven@ubuntu-laptop:~/sources/gmp-5.0.2$ !llvm-nm
llvm-nm .libs/libgmp.a | grep gmpz_init
00000000 T __gmpz_init
00000000 T __gmpz_init2
         U __gmpz_init
00000000 T __gmpz_inits
00000000 T __gmpz_init_set
00000000 T __gmpz_init_set_d
00000000 T __gmpz_init_set_si
00000000 T __gmpz_init_set_str
00000000 T __gmpz_init_set_ui
         U __gmpz_init
         U __gmpz_init_set_ui
         U __gmpz_init2
         U __gmpz_init_set_ui
         U __gmpz_init
         U __gmpz_init_set_str
         U __gmpz_init
         U __gmpz_init2
         U __gmpz_init_set
         U __gmpz_init
         U __gmpz_init_set

So I'm completely at a loss!

It might be worth noting that compiling the test against the library when building with the regular compiler works fine.

EDIT: Got further with this. In version 5.1.1 of this lib they introduced a new configure option '--dissable-assembly', which does a generic C compilation.

The issue now is that while the test runs, it never stops.

It is suggested that I 'disable' the LIKELY and UNLIKELY options in the gmp.h:

https://github.com/kripken/gmp.js/blob/master/gmp-h.in

But I don't see how to 'disable' them as such. Normally there's a 0 or 1 option, but I don't see that here. I don't understand even what this particular option does.

Thanks

Marcos

Solution

  • I got this working in the end. (And indeed for MPFR as well).

    The biggest issue was making sure one used 32 bit options and headers.