error: 'llvm::operator-' has different definitions in different modules

[cjdb]

Details

LLVM hash: 00c2eb2
OS: Ubuntu 20.04.5 (GitHub Actions job)
Build toolchain: LLVM nightly

Config step

$ export CC=/usr/bin/clang-16 CXX=/usr/bin/clang++-16
$ cmake
  -G Ninja
  -S llvm-project/llvm
  -B build
  -DCMAKE_BUILD_TYPE=Release
  -DCMAKE_CROSSCOMPILING=Yes
  -DCMAKE_INSTALL_PREFIX=/tmp/llvm
  -DLLVM_DEFAULT_TARGET_TRIPLE=${{ matrix.target.triple }}
  -DLLVM_ENABLE_LLD=Yes
  -DLLVM_ENABLE_LIBCXX=Yes
  -DLLVM_ENABLE_MODULES=Yes
  -DLLVM_ENABLE_PROJECTS='clang;clang-tools-extra;lld;polly'
  -DLLVM_ENABLE_RUNTIMES='compiler-rt;libcxx;libcxxabi;libunwind'
  -DLLVM_ENABLE_ZLIB=Yes
  -DLLVM_TARGETS_TO_BUILD=${{ matrix.target.name }}

where ${{ matrix.target.triple }} can be x86_64-unknown-linux-gnu or armv7a-unknown-linux-gnu, and ${{ matrix.target.name }} respectively is X86 or ARM.

Diagnostic

/usr/bin/clang++-16 -DGTEST_HAS_RTTI=0 -D_GNU_SOURCE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -I/home/runner/work/lah-toolchain/lah-toolchain/build/lib/Support -I/home/runner/work/lah-toolchain/lah-toolchain/llvm-project/llvm/lib/Support -I/home/runner/work/lah-toolchain/lah-toolchain/build/include -I/home/runner/work/lah-toolchain/lah-toolchain/llvm-project/llvm/include -stdlib=libc++ -fPIC -fno-semantic-interposition -fvisibility-inlines-hidden -Werror=date-time -Werror=unguarded-availability-new -fmodules -fmodules-cache-path=/home/runner/work/lah-toolchain/lah-toolchain/build/module.cache -Xclang -fmodules-local-submodule-visibility -Wall -Wextra -Wno-unused-parameter -Wwrite-strings -Wcast-qual -Wmissing-field-initializers -pedantic -Wno-long-long -Wc++98-compat-extra-semi -Wimplicit-fallthrough -Wcovered-switch-default -Wno-noexcept-type -Wnon-virtual-dtor -Wdelete-non-virtual-dtor -Wsuggest-override -Wno-comment -Wstring-conversion -Wmisleading-indentation -Wctad-maybe-unsupported -fdiagnostics-color -ffunction-sections -fdata-sections  -O3 -DNDEBUG -std=c++17  -fno-exceptions -fno-rtti -MD -MT lib/Support/CMakeFiles/LLVMSupport.dir/APInt.cpp.o -MF lib/Support/CMakeFiles/LLVMSupport.dir/APInt.cpp.o.d -o lib/Support/CMakeFiles/LLVMSupport.dir/APInt.cpp.o -c /home/runner/work/lah-toolchain/lah-toolchain/llvm-project/llvm/lib/Support/APInt.cpp
In module 'LLVM_Utils' imported from /home/runner/work/lah-toolchain/lah-toolchain/llvm-project/llvm/lib/Support/APInt.cpp:14:
/home/runner/work/lah-toolchain/lah-toolchain/llvm-project/llvm/include/llvm/Support/TypeSize.h:214:10: error: 'llvm::operator-' has different definitions in different modules; definition in module 'LLVM_Utils.Support.TypeSize' first difference is return type is 'std::enable_if_t<std::is_signed<U>::value, LeafTy>' (aka 'typename enable_if<std::is_signed<U>::value, type-parameter-0-0>::type')
  friend std::enable_if_t<std::is_signed<U>::value, LeafTy>
         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/home/runner/work/lah-toolchain/lah-toolchain/llvm-project/llvm/include/llvm/Support/TypeSize.h:96:10: note: but in 'LLVM_Utils.Support.TypeSize' found different return type 'typename std::enable_if_t<std::is_signed<U>::value, LeafTy>' (aka 'typename enable_if<std::is_signed<U>::value, type-parameter-0-0>::type')
  friend typename std::enable_if_t<std::is_signed<U>::value, LeafTy>
         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1 error generated.
[11/4440] Building CXX object lib/Support/CMakeFiles/LLVMSupport.dir/APFloat.cpp.o
FAILED: lib/Support/CMakeFiles/LLVMSupport.dir/APFloat.cpp.o 
/usr/bin/clang++-16 -DGTEST_HAS_RTTI=0 -D_GNU_SOURCE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -I/home/runner/work/lah-toolchain/lah-toolchain/build/lib/Support -I/home/runner/work/lah-toolchain/lah-toolchain/llvm-project/llvm/lib/Support -I/home/runner/work/lah-toolchain/lah-toolchain/build/include -I/home/runner/work/lah-toolchain/lah-toolchain/llvm-project/llvm/include -stdlib=libc++ -fPIC -fno-semantic-interposition -fvisibility-inlines-hidden -Werror=date-time -Werror=unguarded-availability-new -fmodules -fmodules-cache-path=/home/runner/work/lah-toolchain/lah-toolchain/build/module.cache -Xclang -fmodules-local-submodule-visibility -Wall -Wextra -Wno-unused-parameter -Wwrite-strings -Wcast-qual -Wmissing-field-initializers -pedantic -Wno-long-long -Wc++98-compat-extra-semi -Wimplicit-fallthrough -Wcovered-switch-default -Wno-noexcept-type -Wnon-virtual-dtor -Wdelete-non-virtual-dtor -Wsuggest-override -Wno-comment -Wstring-conversion -Wmisleading-indentation -Wctad-maybe-unsupported -fdiagnostics-color -ffunction-sections -fdata-sections  -O3 -DNDEBUG -std=c++17  -fno-exceptions -fno-rtti -MD -MT lib/Support/CMakeFiles/LLVMSupport.dir/APFloat.cpp.o -MF lib/Support/CMakeFiles/LLVMSupport.dir/APFloat.cpp.o.d -o lib/Support/CMakeFiles/LLVMSupport.dir/APFloat.cpp.o -c /home/runner/work/lah-toolchain/lah-toolchain/llvm-project/llvm/lib/Support/APFloat.cpp
In module 'LLVM_Utils' imported from /home/runner/work/lah-toolchain/lah-toolchain/llvm-project/llvm/lib/Support/APFloat.cpp:14:
/home/runner/work/lah-toolchain/lah-toolchain/llvm-project/llvm/include/llvm/Support/TypeSize.h:214:10: error: 'llvm::operator-' has different definitions in different modules; definition in module 'LLVM_Utils.Support.TypeSize' first difference is return type is 'std::enable_if_t<std::is_signed<U>::value, LeafTy>' (aka 'typename enable_if<std::is_signed<U>::value, type-parameter-0-0>::type')
  friend std::enable_if_t<std::is_signed<U>::value, LeafTy>
         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/home/runner/work/lah-toolchain/lah-toolchain/llvm-project/llvm/include/llvm/Support/TypeSize.h:96:10: note: but in 'LLVM_Utils.Support.TypeSize' found different return type 'typename std::enable_if_t<std::is_signed<U>::value, LeafTy>' (aka 'typename enable_if<std::is_signed<U>::value, type-parameter-0-0>::type')
  friend typename std::enable_if_t<std::is_signed<U>::value, LeafTy>
         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1 error generated.
[12/44[40](https://github.com/cjdb/lah-toolchain/actions/runs/3306277377/jobs/5457045424#step:7:41)] Building CXX object lib/Demangle/CMakeFiles/LLVMDemangle.dir/ItaniumDemangle.cpp.o
ninja: build stopped: subcommand failed.

[llvmbot]

@llvm/issue-subscribers-clang-modules

[masx200]

[ 37%]: compiling.module.test leetcode_treenode_cpp.freeTreeNode
"C:\\Program Files\\LLVM\\bin\\clang" -c -x c++-module -fmodule-output=build\.gens\leetcode-treenode-cpp\windows\x64\test\rules\modules\cache\ec4a91a6\leetcode_treenode_cpp.freeTreeNode.pcm -fmodule-file=leetcode_treenode_cpp.TreeNode=build\.gens\leetcode-treenode-cpp\windows\x64\test\rules\modules\cache\ec4a91a6\leetcode_treenode_cpp.TreeNode.pcm -Qunused-arguments -m64 -std=c++20 -D__TEST__ -fexceptions -fcxx-exceptions -isystem C:\Users\Administrator\Documents\vcpkg-master\installed\x64-windows-static\include -fmodules-cache-path=build\.gens\leetcode-treenode-cpp\windows\x64\test\rules\modules\cache -fmodule-file=leetcode_treenode_cpp.TreeNode=build\.gens\leetcode-treenode-cpp\windows\x64\test\rules\modules\cache\ec4a91a6\leetcode_treenode_cpp.TreeNode.pcm -o build\.objs\leetcode-treenode-cpp\windows\x64\test\freeTreeNode.ixx.obj freeTreeNode.ixx
error: @programdir\modules\private\async\runjobs.lua:256: @programdir\rules\c++\modules\modules_support\clang.lua:270: @programdir\modules\core\tools\gcc.lua:721: In file included from traversalTreeNode.ixx:2:
In file included from C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Tools\MSVC\14.35.32215\include\vector:11:
In file included from C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Tools\MSVC\14.35.32215\include\xmemory:14:
In file included from C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Tools\MSVC\14.35.32215\include\new:11:
In file included from C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Tools\MSVC\14.35.32215\include\exception:12:
C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Tools\MSVC\14.35.32215\include\type_traits:2186:19: error: 'std::hash' has different definitions in different modules; first difference is defined here found method '_Do_hash' with no body
    static size_t _Do_hash(const _Kty& _Keyval) noexcept {
    ~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Tools\MSVC\14.35.32215\include\type_traits:2186:19: note: but in 'leetcode_treenode_cpp.TreeNode.<global>' found method '_Do_hash' with body
    static size_t _Do_hash(const _Kty& _Keyval) noexcept {
    ~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from traversalTreeNode.ixx:2:
In file included from C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Tools\MSVC\14.35.32215\include\vector:11:
In file included from C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Tools\MSVC\14.35.32215\include\xmemory:14:
In file included from C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Tools\MSVC\14.35.32215\include\new:11:
In file included from C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Tools\MSVC\14.35.32215\include\exception:12:
C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Tools\MSVC\14.35.32215\include\type_traits:2167:23: error: 'std::_Conditionally_enabled_hash' has different definitions in different modules; first difference is defined here found method 'operator()' with no body
    _NODISCARD size_t operator()(const _Kty& _Keyval) const
               ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Tools\MSVC\14.35.32215\include\type_traits:2167:23: note: but in 'leetcode_treenode_cpp.TreeNode.<global>' found method 'operator()' with body
    _NODISCARD size_t operator()(const _Kty& _Keyval) const
               ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
2 errors generated.

[dwblaikie]

A reduced test case would eb nice - though they are a pain to produce for modular builds.

(is the expectation that this is a bug in LLVM's source, or in clang's modules implementation, or something else?)

[davidstone]

@masx200: Your issue is #60027.

I wouldn't be surprised if the original issue is also that issue.