Clang: Add support for passing VFS arguments
diff --git a/Help/manual/cmake-variables.7.rst b/Help/manual/cmake-variables.7.rst
index 4ce8365..d780a65 100644
--- a/Help/manual/cmake-variables.7.rst
+++ b/Help/manual/cmake-variables.7.rst
@@ -158,6 +158,7 @@
/variable/CMAKE_AUTOMOC_RELAXED_MODE
/variable/CMAKE_BACKWARDS_COMPATIBILITY
/variable/CMAKE_BUILD_TYPE
+ /variable/CMAKE_CLANG_VFS_OVERLAY
/variable/CMAKE_CODEBLOCKS_COMPILER_ID
/variable/CMAKE_CODEBLOCKS_EXCLUDE_EXTERNAL_FILES
/variable/CMAKE_CODELITE_USE_TARGETS
diff --git a/Help/release/dev/clang-cl-vfs.rst b/Help/release/dev/clang-cl-vfs.rst
new file mode 100644
index 0000000..40b19ef
--- /dev/null
+++ b/Help/release/dev/clang-cl-vfs.rst
@@ -0,0 +1,6 @@
+clang-cl-vfs
+------------
+
+* A :variable:`CMAKE_CLANG_VFS_OVERLAY` variable was added to tell
+ Clang to use a VFS overlay to support the Windows SDK when
+ cross-compiling from hosts with case-sensitive filesystems.
diff --git a/Help/variable/CMAKE_CLANG_VFS_OVERLAY.rst b/Help/variable/CMAKE_CLANG_VFS_OVERLAY.rst
new file mode 100644
index 0000000..56ac328
--- /dev/null
+++ b/Help/variable/CMAKE_CLANG_VFS_OVERLAY.rst
@@ -0,0 +1,9 @@
+CMAKE_CLANG_VFS_OVERLAY
+-----------------------
+
+.. versionadded:: 3.19
+
+When cross compiling for windows with clang-cl, this variable can be an
+absolute path pointing to a clang virtual file system yaml file, which
+will enable clang-cl to resolve windows header names on a case sensitive
+file system.
diff --git a/Source/cmLocalGenerator.cxx b/Source/cmLocalGenerator.cxx
index 4d39312..dc3bf47 100644
--- a/Source/cmLocalGenerator.cxx
+++ b/Source/cmLocalGenerator.cxx
@@ -1938,6 +1938,9 @@
this->AddConfigVariableFlags(flags, cmStrCat("CMAKE_", lang, "_FLAGS"),
config);
+ std::string const& compiler = this->Makefile->GetSafeDefinition(
+ cmStrCat("CMAKE_", lang, "_COMPILER_ID"));
+
if (lang == "Swift") {
if (cmProp v = target->GetProperty("Swift_LANGUAGE_VERSION")) {
if (cmSystemTools::VersionCompare(
@@ -1951,9 +1954,6 @@
target->AddCUDAArchitectureFlags(flags);
target->AddCUDAToolkitFlags(flags);
- std::string const& compiler =
- this->Makefile->GetSafeDefinition("CMAKE_CUDA_COMPILER_ID");
-
if (compiler == "Clang") {
bool separable = target->GetPropertyAsBool("CUDA_SEPARABLE_COMPILATION");
@@ -1965,7 +1965,24 @@
}
}
}
-
+ // Add VFS Overlay for Clang compiliers
+ if (compiler == "Clang") {
+ if (const char* vfsOverlay =
+ this->Makefile->GetDefinition("CMAKE_CLANG_VFS_OVERLAY")) {
+ std::string const& compilerSimulateId =
+ this->Makefile->GetSafeDefinition(
+ cmStrCat("CMAKE_", lang, "_SIMULATE_ID"));
+ if (compilerSimulateId == "MSVC") {
+ this->AppendCompileOptions(
+ flags,
+ std::vector<std::string>{ "-Xclang", "-ivfsoverlay", "-Xclang",
+ vfsOverlay });
+ } else {
+ this->AppendCompileOptions(
+ flags, std::vector<std::string>{ "-ivfsoverlay", vfsOverlay });
+ }
+ }
+ }
// Add MSVC runtime library flags. This is activated by the presence
// of a default selection whether or not it is overridden by a property.
cmProp msvcRuntimeLibraryDefault =
