Cannot find std module of gcc in spack

[hieubnt235]

Hi, I use xmake with gcc installed through spack.

The libstdc++.modules.json is realize correctly.

$ gcc -print-file-name=libstdc++.modules.json

/home/user/spack/opt/spack/linux-x86_64_v3/gcc-15.2.0-xsbqcqirlm75iar5hx5nckpzsrfda5bo/lib/gcc/x86_64-pc-linux-gnu/15.2.0/../../../../lib64/libstdc++.modules.json

But it cannot be found when compile

xmake build -v
[ 13%]: <mod> compiling.bmi.release module1
checking for flags (gcc_module_only) ... ok
/home/user/spack/var/spack/environments/devenv/.spack-env/view/bin/gcc -c -m64 -fvisibility=hidden -fvisibility-inlines-hidden -O3 -std=c++23 -fmodules-ts -D_GLIBCXX_USE_CXX11_ABI=0 -DNDEBUG -fmodule-mapper=/tmp/.xmake1000/251020/mod/src/module1.cppm -x c++ -fmodule-only -o build/.objs/mod/linux/x86_64/release/src/module1.cppm.o src/module1.cppm
checking for flags (-fdiagnostics-color=always) ... ok
error: module dependency std required for src/module1.cpp not found

Is there a guide to help this problem ?

Thank you.

[waruqi]

you can debug here.

xmake/xmake/rules/c++/modules/gcc/support.lua

Line 140 in 405221a

return os.iorunv(compinst:program(), {"-print-file-name=libstdc++.modules.json"}, {envs = compinst:runenvs()})

[hieubnt235]

Hi, I have some questions. Does xmake only support clang+libcxx or gcc+libstdcxx ? Is there the way to use clang + libstdcxx instead? Because when ever I use --toolchain==llvm, it's always search for libc++ and I can't find the way to use with libstdc++.

Also, is there a way to specify ...modules.json directly? Because some manager tool does not ship the whole llvm or gcc together.

[waruqi]

Hi, I have some questions. Does xmake only support clang+libcxx or gcc+libstdcxx ? Is there the way to use clang + libstdcxx instead? Because when ever I use --toolchain==llvm, it's always search for libc++ and I can't find the way to use with libstdc++.

you can use libstdcxx or msstl for clang

xmake f --toolchain=llvm --runtimes=stdc++_shared

xmake/xmake/rules/c++/modules/support.lua

Line 76 in 405221a

elseif target:has_runtime("stdc++_shared", "stdc++_static") then

xmake/xmake/rules/c++/modules/clang/support.lua

Line 267 in 405221a

elseif cpplib == "stdc++" then

[waruqi]

Also, is there a way to specify ...modules.json directly? Because some manager tool does not ship the whole llvm or gcc together.

no way

[hieubnt235]

xmake f --toolchain=llvm --runtimes=stdc++_shared

I know this, but I want to specify the directory of stdlibc++ or g++. It just use the default g++. But I have multiple g++ version in my system. With llvm I can use --sdk=/path/to/llvm. How about the case of stdlibc++ or g++ ?