CMakeDetermineCompilerId: Add notion of "simulated" id/version

Some compilers try to simulate other compilers as a drop-in replacement
supporting all the same command-line options and predefined preprocessor
macros.  In such cases it will be useful to have CMake load the compiler
information files for the simulated compiler instead of duplicating the
information.  Teach CMakeDetermineCompilerId to extract the simulated
compiler id and version when the compiler id detection provides it.

1 files changed, 22 insertions, 0 deletions

diff --git a/Source/cmDocumentVariables.cxx b/Source/cmDocumentVariables.cxx
index c4f6216..2fafef5 100644
--- a/Source/cmDocumentVariables.cxx
+++ b/Source/cmDocumentVariables.cxx
@@ -1659,6 +1659,28 @@ void cmDocumentVariables::DefineVariables(cmake* cm)
      "Variables for Languages");
 
   cm->DefineProperty
+    ("CMAKE_<LANG>_SIMULATE_ID", cmProperty::VARIABLE,
+     "Identification string of \"simulated\" compiler.",
+     "Some compilers simulate other compilers to serve as drop-in "
+     "replacements.  "
+     "When CMake detects such a compiler it sets this variable to what "
+     "would have been the CMAKE_<LANG>_COMPILER_ID for the simulated "
+     "compiler.",
+     false,
+     "Variables for Languages");
+
+  cm->DefineProperty
+    ("CMAKE_<LANG>_SIMULATE_VERSION", cmProperty::VARIABLE,
+     "Version string of \"simulated\" compiler.",
+     "Some compilers simulate other compilers to serve as drop-in "
+     "replacements.  "
+     "When CMake detects such a compiler it sets this variable to what "
+     "would have been the CMAKE_<LANG>_COMPILER_VERSION for the simulated "
+     "compiler.",
+     false,
+     "Variables for Languages");
+
+  cm->DefineProperty
     ("CMAKE_<LANG>_SIZEOF_DATA_PTR", cmProperty::VARIABLE,
      "Size of pointer-to-data types for language <LANG>.",
      "This holds the size (in bytes) of pointer-to-data types in the target "