macOS: binaryen port sometimes builds with Emscripten instead of native compiler

[rgov]

I passed -s WASM=1 to emcc and it kicked off a build of binaryen:

INFO:root:generating port: binaryen_tag_version_44.txt... (this will be cached in "/Users/rzg/.emscripten_cache/asmjs/binaryen_tag_version_44.txt" for subsequent builds)
INFO:root:building port: binaryen
-- Building with -std=c++11
CMake Warning at CMakeLists.txt:132 (message):
  Unknown target architecture!

-- Building with -Wall
-- Building with -Werror
-- Building with -Wextra
-- Building with -Wno-unused-parameter
-- Building with -fno-omit-frame-pointer
-- Building with -fPIC
-- Building with -O2
-- Building with -UNDEBUG
-- Configuring done
CMake Warning (dev):
  Policy CMP0042 is not set: MACOSX_RPATH is enabled by default.  Run "cmake
  --help-policy CMP0042" for policy details.  Use the cmake_policy command to
  set the policy and suppress this warning.

  MACOSX_RPATH is not specified for the following targets:

   binaryen

This warning is for project developers.  Use -Wno-dev to suppress it.

-- Generating done
-- Build files have been written to: /Users/rzg/.emscripten_ports/binaryen/binaryen-version_44
[  1%] Linking CXX static library ../../lib/libasmjs.a
[  2%] Linking CXX static library ../../lib/libir.a
[  3%] Linking CXX static library ../../lib/libwasm.a
[  4%] Linking CXX static library ../../lib/libcfg.a
fatal error: /Applications/Xcode-beta.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/ar: fatal error in /Applications/Xcode-beta.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/ranlib
fatal error: /Applications/Xcode-beta.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/ar: fatal error in /Applications/Xcode-beta.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/ranlib
fatal error: /Applications/Xcode-beta.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/ar: fatal error in /Applications/Xcode-beta.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/ranlib
make[5]: *** [lib/libasmjs.a] Error 1
make[5]: *** Deleting file `lib/libasmjs.a'
make[5]: *** [lib/libir.a] Error 1
make[5]: *** Deleting file `lib/libir.a'
make[4]: *** [src/ir/CMakeFiles/ir.dir/all] Error 2
make[4]: *** Waiting for unfinished jobs....
make[4]: *** [src/asmjs/CMakeFiles/asmjs.dir/all] Error 2
make[5]: *** [lib/libcfg.a] Error 1
make[5]: *** Deleting file `lib/libcfg.a'
make[4]: *** [src/cfg/CMakeFiles/cfg.dir/all] Error 2
fatal error: /Applications/Xcode-beta.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/ar: fatal error in /Applications/Xcode-beta.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/ranlib
make[5]: *** [lib/libwasm.a] Error 1
make[5]: *** Deleting file `lib/libwasm.a'
make[4]: *** [src/wasm/CMakeFiles/wasm.dir/all] Error 2
make[3]: *** [all] Error 2

[rgov]

It seems to build OK if I just clone the repo from WebAssembly/binaryen.

[rgov]

When it messes up, the CMakeCache.txt file says CMAKE_CXX_COMPILER is pointed to em++. When it works, it's using the regular compiler.

[kripken]

Was this maybe when using emmake or emconfigure? Or were the env vars CC/CXX set to emcc/em++ manually? It seems like that could cause this. If it's the cause, we should probably prevent that or at least warn about it.

[rgov]

I was doing emcmake cmake {options} .. && cmake --build .

[kripken]

What does cmake --build do? Perhaps we incorrectly detect it as running cmake's configuration stage.

[rgov]

I don't think I was running emcmake -- build . just regular cmake --build . but anyway the command invokes the build tool. It's useful so you don't have to remember how to invoke the specific generator.

[kripken]

I see. Not sure what could cause that, then, but I admit I don't know much about MacOS as well as CMake.

Maybe you can get a set of concrete steps that reproduce this problem consistently?

[stale[bot]]

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