cmake: Always use all compilers for LLVM (fixes #10249)

3 files changed, 14 insertions, 4 deletions

diff --git a/mesonbuild/dependencies/cmake.py b/mesonbuild/dependencies/cmake.py
index cff0e58..e9a4aa3 100644
--- a/mesonbuild/dependencies/cmake.py
+++ b/mesonbuild/dependencies/cmake.py
@@ -76,10 +76,10 @@ class CMakeDependency(ExternalDependency):
         # one module
         return module
 
-    def __init__(self, name: str, environment: 'Environment', kwargs: T.Dict[str, T.Any], language: T.Optional[str] = None) -> None:
+    def __init__(self, name: str, environment: 'Environment', kwargs: T.Dict[str, T.Any], language: T.Optional[str] = None, force_use_global_compilers: bool = False) -> None:
         # Gather a list of all languages to support
         self.language_list = []  # type: T.List[str]
-        if language is None:
+        if language is None or force_use_global_compilers:
             compilers = None
             if kwargs.get('native', False):
                 compilers = environment.coredata.compilers.build
diff --git a/mesonbuild/dependencies/data/CMakeListsLLVM.txt b/mesonbuild/dependencies/data/CMakeListsLLVM.txt
index 9d3e412..da23189 100644
--- a/mesonbuild/dependencies/data/CMakeListsLLVM.txt
+++ b/mesonbuild/dependencies/data/CMakeListsLLVM.txt
@@ -1,4 +1,3 @@
-cmake_minimum_required(VERSION ${CMAKE_MAJOR_VERSION}.${CMAKE_MINOR_VERSION}.${CMAKE_PATCH_VERSION} )
 
 set(PACKAGE_FOUND FALSE)
 
diff --git a/mesonbuild/dependencies/dev.py b/mesonbuild/dependencies/dev.py
index 793b38a..49d62a5 100644
--- a/mesonbuild/dependencies/dev.py
+++ b/mesonbuild/dependencies/dev.py
@@ -403,7 +403,18 @@ class LLVMDependencyCMake(CMakeDependency):
     def __init__(self, name: str, env: 'Environment', kwargs: T.Dict[str, T.Any]) -> None:
         self.llvm_modules = stringlistify(extract_as_list(kwargs, 'modules'))
         self.llvm_opt_modules = stringlistify(extract_as_list(kwargs, 'optional_modules'))
-        super().__init__(name, env, kwargs, language='cpp')
+
+        compilers = None
+        if kwargs.get('native', False):
+            compilers = env.coredata.compilers.build
+        else:
+            compilers = env.coredata.compilers.host
+        if not compilers or not all(x in compilers for x in ('c', 'cpp')):
+            self.is_found = False
+            mlog.warning('The LLVM dependency was not found via CMake since both a C and C++ compiler are required.')
+            return
+
+        super().__init__(name, env, kwargs, language='cpp', force_use_global_compilers=True)
 
         # Cmake will always create a statically linked binary, so don't use
         # cmake if dynamic is required