echo/CMake
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

cxxmodules: give a reason for unavailability of import std

Browse Source 
If the `CMAKE_CXX<STANDARD>_COMPILER_IMPORT_STD_NOT_FOUND_MESSAGE`
variable is set, include its value in the error message.
This commit is contained in:
Ben Boeckel 2024-05-01 23:06:20 -04:00
parent de9faaf0a3
commit 6dad18f060
5 changed files with 61 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

15
Modules/Compiler/CMakeCommonCompilerMacros.cmake
View File

@ -211,6 +211,9 @@ function(cmake_create_cxx_import_std std variable)
26)
list(FIND _cmake_supported_import_std_features "${std}" _cmake_supported_import_std_idx)
if (_cmake_supported_import_std_idx EQUAL "-1")
set("${variable}"
"set(CMAKE_CXX${std}_COMPILER_IMPORT_STD_NOT_FOUND_MESSAGE \"Unsupported C++ standard: C++${std}\")\n"
PARENT_SCOPE)
return ()
endif ()
# If the target exists, skip. A toolchain file may have provided it.
@ -219,14 +222,23 @@ function(cmake_create_cxx_import_std std variable)
endif ()
# The generator must support imported C++ modules.
if (NOT CMAKE_GENERATOR MATCHES "Ninja")
set("${variable}"
"set(CMAKE_CXX${std}_COMPILER_IMPORT_STD_NOT_FOUND_MESSAGE \"Unsupported generator: ${CMAKE_GENERATOR}\")\n"
PARENT_SCOPE)
return ()
endif ()
# Check if the compiler understands how to `import std;`.
include("${CMAKE_ROOT}/Modules/Compiler/${CMAKE_CXX_COMPILER_ID}-CXX-CXXImportStd.cmake" OPTIONAL RESULT_VARIABLE _cmake_import_std_res)
if (NOT _cmake_import_std_res)
set("${variable}"
"set(CMAKE_CXX${std}_COMPILER_IMPORT_STD_NOT_FOUND_MESSAGE \"Toolchain does not support discovering `import std` support\")\n"
PARENT_SCOPE)
return ()
endif ()
if (NOT COMMAND _cmake_cxx_import_std)
set("${variable}"
"set(CMAKE_CXX${std}_COMPILER_IMPORT_STD_NOT_FOUND_MESSAGE \"Toolchain does not provide `import std` discovery command\")\n"
PARENT_SCOPE)
return ()
endif ()
@ -237,6 +249,9 @@ function(cmake_create_cxx_import_std std variable)
"CxxImportStd"
_cmake_supported_import_std_experimental)
if (NOT _cmake_supported_import_std_experimental)
set("${variable}"
"set(CMAKE_CXX${std}_COMPILER_IMPORT_STD_NOT_FOUND_MESSAGE \"Experimental `import std` support not enabled when detecting toolchain\")\n"
PARENT_SCOPE)
return ()
endif ()

15
Modules/Compiler/Clang-CXX-CXXImportStd.cmake
View File

@ -14,11 +14,17 @@ function (_cmake_cxx_import_std std variable)
OUTPUT_STRIP_TRAILING_WHITESPACE
ERROR_STRIP_TRAILING_WHITESPACE)
if (_clang_libcxx_modules_json_file_res)
set("${variable}"
"set(CMAKE_CXX${std}_COMPILER_IMPORT_STD_NOT_FOUND_MESSAGE \"Could not find `libc++.modules.json` resource\")\n"
PARENT_SCOPE)
return ()
endif ()
# Without this file, we do not have modules installed.
if (NOT EXISTS "${_clang_libcxx_modules_json_file}")
set("${variable}"
"set(CMAKE_CXX${std}_COMPILER_IMPORT_STD_NOT_FOUND_MESSAGE \"`libc++.modules.json` resource does not exist\")\n"
PARENT_SCOPE)
return ()
endif ()
@ -26,6 +32,9 @@ function (_cmake_cxx_import_std std variable)
# The original PR had a key spelling mismatch internally. Do not support it
# and instead require a release known to have the fix.
# https://github.com/llvm/llvm-project/pull/83036
set("${variable}"
"set(CMAKE_CXX${std}_COMPILER_IMPORT_STD_NOT_FOUND_MESSAGE \"LLVM 18.1.2 is required for `libc++.modules.json` format fix\")\n"
PARENT_SCOPE)
return ()
endif ()
@ -34,12 +43,18 @@ function (_cmake_cxx_import_std std variable)
string(JSON _clang_modules_json_revision GET "${_clang_libcxx_modules_json}" "revision")
# Require version 1.
if (NOT _clang_modules_json_version EQUAL "1")
set("${variable}"
"set(CMAKE_CXX${std}_COMPILER_IMPORT_STD_NOT_FOUND_MESSAGE \"`libc++.modules.json` version ${_clang_modules_json_version}.${_clang_modules_json_revision} is not recognized\")\n"
PARENT_SCOPE)
return ()
endif ()
string(JSON _clang_modules_json_nmodules LENGTH "${_clang_libcxx_modules_json}" "modules")
# Don't declare the target without any modules.
if (NOT _clang_modules_json_nmodules)
set("${variable}"
"set(CMAKE_CXX${std}_COMPILER_IMPORT_STD_NOT_FOUND_MESSAGE \"`libc++.modules.json` does not list any available modules\")\n"
PARENT_SCOPE)
return ()
endif ()

12
Modules/Compiler/MSVC-CXX-CXXImportStd.cmake
View File

@ -12,6 +12,9 @@ function (_cmake_cxx_import_std std variable)
NO_CACHE)
# Without this file, we do not have modules installed.
if (NOT EXISTS "${_msvc_modules_json_file}")
set("${variable}"
"set(CMAKE_CXX${std}_COMPILER_IMPORT_STD_NOT_FOUND_MESSAGE \"Could not find `modules.json` resource\")\n"
PARENT_SCOPE)
return ()
endif ()
@ -20,18 +23,27 @@ function (_cmake_cxx_import_std std variable)
string(JSON _msvc_json_revision GET "${_msvc_modules_json}" "revision")
# Require version 1.
if (NOT _msvc_json_version EQUAL "1")
set("${variable}"
"set(CMAKE_CXX${std}_COMPILER_IMPORT_STD_NOT_FOUND_MESSAGE \"`modules.json` version ${_msvc_json_version}.${_msvc_json_revision} is not recognized\")\n"
PARENT_SCOPE)
return ()
endif ()
string(JSON _msvc_json_library GET "${_msvc_modules_json}" "library")
# Bail if we don't understand the library.
if (NOT _msvc_json_library STREQUAL "microsoft/STL")
set("${variable}"
"set(CMAKE_CXX${std}_COMPILER_IMPORT_STD_NOT_FOUND_MESSAGE \"`modules.json` library `${_msvc_json_library}` is not recognized\")\n"
PARENT_SCOPE)
return ()
endif ()
string(JSON _msvc_json_nmodules LENGTH "${_msvc_modules_json}" "module-sources")
# Don't declare the target without any modules.
if (NOT _msvc_json_nmodules)
set("${variable}"
"set(CMAKE_CXX${std}_COMPILER_IMPORT_STD_NOT_FOUND_MESSAGE \"`modules.json` does not list any available modules\")\n"
PARENT_SCOPE)
return ()
endif ()

19
Source/cmGeneratorTarget.cxx
View File

@ -8569,15 +8569,22 @@ bool cmGeneratorTarget::ApplyCXXStdTargets()
continue;
}
auto const targetName = cmStrCat(
"__CMAKE::CXX", standardResolver.GetLevelString("CXX", *explicitLevel));
auto const stdLevel =
standardResolver.GetLevelString("CXX", *explicitLevel);
auto const targetName = cmStrCat("__CMAKE::CXX", stdLevel);
if (!this->Makefile->FindTargetToUse(targetName)) {
auto basicReason = this->Makefile->GetDefinition(cmStrCat(
"CMAKE_CXX", stdLevel, "_COMPILER_IMPORT_STD_NOT_FOUND_MESSAGE"));
std::string reason;
if (!basicReason.IsEmpty()) {
reason = cmStrCat(" Reason:\n ", basicReason);
}
this->Makefile->IssueMessage(
MessageType::FATAL_ERROR,
cmStrCat(
R"(The "CXX_MODULE_STD" property on the target ")", this->GetName(),
"\" requires that the \"", targetName,
"\" target exist, but it was not provided by the toolchain."));
cmStrCat(R"(The "CXX_MODULE_STD" property on the target ")",
this->GetName(), "\" requires that the \"", targetName,
"\" target exist, but it was not provided by the toolchain.",
reason));
break;
}

7
Tests/RunCMake/CXXModules/NoCXX23TargetRequired-stderr.txt
View File

@ -1,4 +1,9 @@
CMake Error in CMakeLists.txt:
The "CXX_MODULE_STD" property on the target "nocxx23target" requires that
the "__CMAKE::CXX23" target exist, but it was not provided by the
toolchain.
toolchain. Reason:
(Toolchain does not support discovering `import std` support|Experimental `import std` support not enabled when detecting toolchain|Unsupported generator: [^\n]*)
CMake Generate step failed. Build files cannot be regenerated correctly.