Trouble linking against -lGL in test

[lannoene]

Hello! I am getting an error trying to compile the minimal_webgl test (and anything that links against -lGL). Am I doing something wrong? Here's the info:

Version:

emcc (Emscripten gcc/clang-like replacement + linker emulating GNU ld) 4.0.16-git (09534bba7f0ee767bf6f6f8cb5b7bf9519b8d63a)
clang version 22.0.0git
Target: wasm32-unknown-emscripten
Thread model: posix
InstalledDir: C:/devkitPro/msys2/clang64/opt/emscripten-llvm/bin

Here's what happens when I try to make it:

$ mingw32-make
[ 33%] Building C object CMakeFiles/minimal_webgl.dir/main.c.o
[ 66%] Building C object CMakeFiles/minimal_webgl.dir/webgl.c.o
[100%] Linking C executable minimal_webgl.html
 "C:/devkitPro/msys2/clang64/opt/emscripten-llvm/bin/clang.exe" --version
 "C:/devkitPro/msys2/clang64/bin/node.exe" C:/devkitPro/msys2/clang64/lib/emscripten/tools/compiler.mjs - --symbols-only
error: C:/devkitPro/msys2/clang64/lib/emscripten/src/lib/libwebgl.js: failure to execute JS library "C:/devkitPro/msys2/clang64/lib/emscripten/src/lib/libwebgl.js":
Internal compiler error JS compiler
Please create a bug report at https://github.com/emscripten-core/emscripten/issues/
with a log of the build and the input files used to run. Exception message: "C:/devkitPro/msys2/clang64/lib/emscripten/src/lib/libwebgl.js:1


SyntaxError: Identifier 'GL_POOL_TEMP_BUFFERS_SIZE' has already been declared
    at Script.runInContext (node:vm:149:12)
    at Module.runInContext (node:vm:301:6)
    at runInMacroContext (file:///C:/devkitPro/msys2/clang64/lib/emscripten/src/utility.mjs:328:13)
    at file:///C:/devkitPro/msys2/clang64/lib/emscripten/src/parseTools.mjs:43:19
    at String.replace (<anonymous>)
    at processMacros (file:///C:/devkitPro/msys2/clang64/lib/emscripten/src/parseTools.mjs:42:17)
    at Object.load (file:///C:/devkitPro/msys2/clang64/lib/emscripten/src/modules.mjs:288:21)
    at Module.runJSify (file:///C:/devkitPro/msys2/clang64/lib/emscripten/src/jsifier.mjs:360:18)
    at file:///C:/devkitPro/msys2/clang64/lib/emscripten/tools/compiler.mjs:97:17
emcc: error: 'C:/devkitPro/msys2/clang64/bin/node.exe C:/devkitPro/msys2/clang64/lib/emscripten/tools/compiler.mjs - --symbols-only' failed (returned 1)
mingw32-make[2]: *** [CMakeFiles\minimal_webgl.dir\build.make:116: minimal_webgl.html] Error 1
mingw32-make[1]: *** [CMakeFiles\Makefile2:86: CMakeFiles/minimal_webgl.dir/all] Error 2
mingw32-make: *** [Makefile:90: all] Error 2

[sbc100]

Can you run make with V=1 ? (Or VERBOSE=1?) So we can see the full failing command.

What I think is happening here is that the libgl library is being processed twice but it would be good to see exactly how you triggered this.

[sbc100]

I think the problem is almost certainly some kind of issue with windows pathname canonicalization.

See

emscripten/src/modules.mjs

Lines 211 to 212 in 22719c1

	// Deduplicate libraries to avoid processing any library file multiple times
	libraries = libraries.filter((item, pos) => libraries.indexOf(item) == pos);

. Can you use console.error to print libraries before and after this line. I'm guessing there are some pathnames with different capitialization or path specifiers.

[lannoene]

It appears you were correct. It's due to the difference in forward slashes and backslashes.

[
  'C:\\devkitPro\\msys2\\clang64\\lib\\emscripten\\src\\lib\\libint53.js',
  'C:\\devkitPro\\msys2\\clang64\\lib\\emscripten\\src\\lib\\libcore.js',
  'C:\\devkitPro\\msys2\\clang64\\lib\\emscripten\\src\\lib\\libsigs.js',
  'C:\\devkitPro\\msys2\\clang64\\lib\\emscripten\\src\\lib\\libccall.js',
  'C:\\devkitPro\\msys2\\clang64\\lib\\emscripten\\src\\lib\\libaddfunction.js',
  'C:\\devkitPro\\msys2\\clang64\\lib\\emscripten\\src\\lib\\libgetvalue.js',
  'C:\\devkitPro\\msys2\\clang64\\lib\\emscripten\\src\\lib\\libmath.js',
  'C:\\devkitPro\\msys2\\clang64\\lib\\emscripten\\src\\lib\\libpath.js',
  'C:\\devkitPro\\msys2\\clang64\\lib\\emscripten\\src\\lib\\libstrings.js',
  'C:\\devkitPro\\msys2\\clang64\\lib\\emscripten\\src\\lib\\libhtml5.js',
  'C:\\devkitPro\\msys2\\clang64\\lib\\emscripten\\src\\lib\\libstack_trace.js',
  'C:\\devkitPro\\msys2\\clang64\\lib\\emscripten\\src\\lib\\libwasi.js',
  'C:\\devkitPro\\msys2\\clang64\\lib\\emscripten\\src\\lib\\libeventloop.js',
  'C:\\devkitPro\\msys2\\clang64\\lib\\emscripten\\src\\lib\\libpromise.js',
  'C:\\devkitPro\\msys2\\clang64\\lib\\emscripten\\src\\lib\\libexceptions.js',
  'C:\\devkitPro\\msys2\\clang64\\lib\\emscripten\\src\\lib\\libtime.js',
  'C:\\devkitPro\\msys2\\clang64\\lib\\emscripten\\src\\lib\\libsyscall.js',
  'C:\\devkitPro\\msys2\\clang64\\lib\\emscripten\\src\\lib\\libwebgl.js',
  'C:\\devkitPro\\msys2\\clang64\\lib\\emscripten\\src\\lib\\libwebgl2.js',
  'C:\\devkitPro\\msys2\\clang64\\lib\\emscripten\\src\\lib\\liblegacy.js',
  'C:/devkitPro/msys2/clang64/lib/emscripten/src/lib/libpthread_stub.js',
  'C:/devkitPro/msys2/clang64/lib/emscripten/test/minimal_webgl/library_js.js',
  'C:/devkitPro/msys2/clang64/lib/emscripten/src/lib/libwebgl.js',
  'C:/devkitPro/msys2/clang64/lib/emscripten/src/lib/libhtml5_webgl.js'
]
[
  'C:\\devkitPro\\msys2\\clang64\\lib\\emscripten\\src\\lib\\libint53.js',
  'C:\\devkitPro\\msys2\\clang64\\lib\\emscripten\\src\\lib\\libcore.js',
  'C:\\devkitPro\\msys2\\clang64\\lib\\emscripten\\src\\lib\\libsigs.js',
  'C:\\devkitPro\\msys2\\clang64\\lib\\emscripten\\src\\lib\\libccall.js',
  'C:\\devkitPro\\msys2\\clang64\\lib\\emscripten\\src\\lib\\libaddfunction.js',
  'C:\\devkitPro\\msys2\\clang64\\lib\\emscripten\\src\\lib\\libgetvalue.js',
  'C:\\devkitPro\\msys2\\clang64\\lib\\emscripten\\src\\lib\\libmath.js',
  'C:\\devkitPro\\msys2\\clang64\\lib\\emscripten\\src\\lib\\libpath.js',
  'C:\\devkitPro\\msys2\\clang64\\lib\\emscripten\\src\\lib\\libstrings.js',
  'C:\\devkitPro\\msys2\\clang64\\lib\\emscripten\\src\\lib\\libhtml5.js',
  'C:\\devkitPro\\msys2\\clang64\\lib\\emscripten\\src\\lib\\libstack_trace.js',
  'C:\\devkitPro\\msys2\\clang64\\lib\\emscripten\\src\\lib\\libwasi.js',
  'C:\\devkitPro\\msys2\\clang64\\lib\\emscripten\\src\\lib\\libeventloop.js',
  'C:\\devkitPro\\msys2\\clang64\\lib\\emscripten\\src\\lib\\libpromise.js',
  'C:\\devkitPro\\msys2\\clang64\\lib\\emscripten\\src\\lib\\libexceptions.js',
  'C:\\devkitPro\\msys2\\clang64\\lib\\emscripten\\src\\lib\\libtime.js',
  'C:\\devkitPro\\msys2\\clang64\\lib\\emscripten\\src\\lib\\libsyscall.js',
  'C:\\devkitPro\\msys2\\clang64\\lib\\emscripten\\src\\lib\\libwebgl.js',
  'C:\\devkitPro\\msys2\\clang64\\lib\\emscripten\\src\\lib\\libwebgl2.js',
  'C:\\devkitPro\\msys2\\clang64\\lib\\emscripten\\src\\lib\\liblegacy.js',
  'C:/devkitPro/msys2/clang64/lib/emscripten/src/lib/libpthread_stub.js',
  'C:/devkitPro/msys2/clang64/lib/emscripten/test/minimal_webgl/library_js.js',
  'C:/devkitPro/msys2/clang64/lib/emscripten/src/lib/libwebgl.js',
  'C:/devkitPro/msys2/clang64/lib/emscripten/src/lib/libhtml5_webgl.js'
]

[lannoene]

I fixed it by adding this line:

libraries = libraries.map(e => {return e.split(/\\/).join("/");});

[sbc100]

I imagine the correct fix is to use path.normalize(..) , but I wonder if we can find a way to reproduce this in our CI somehow.

I wonder if it requires the use of msys to reproduce? What version of python are you using the run emcc? And what version of node? Does the issue show up if you use the emsdk bundled SDK?