LCC: Add dedicated support for MCST LCC compiler

Divert LCC compiler as a new one, instead of treating it as GNU.

Since old times, Elbrus C/C++/Fortran Compiler (LCC) by MCST has been
passing checks for GNU compilers, so it has been identified as GNU.
Now, with intent of seriously upstreaming its support, it has been
added as a separate LCC compiler, and its version displays not a
supported GCC version, but LCC version itself (e.g. LCC 1.25.19 instead
of GNU 7.3.0).

This commit adds its support for detection, and also converts basically
every check like 'is this compiler GNU?' to 'is this compiler GNU or
LCC?'. The only places where this check is untouched, is where it
regards other platforms where LCC is unavailable (primarily non-Linux),
and where it REALLY differs from GNU compiler.

Note: this transition may break software that are already ported to
Elbrus, but hardly relies that LCC will be detected as GNU; still such
software is not known.

1 files changed, 37 insertions, 0 deletions

diff --git a/Modules/Compiler/LCC-FindBinUtils.cmake b/Modules/Compiler/LCC-FindBinUtils.cmake
new file mode 100644
index 0000000..4dcdd53
--- /dev/null
+++ b/Modules/Compiler/LCC-FindBinUtils.cmake
@@ -0,0 +1,37 @@
+if(NOT DEFINED _CMAKE_PROCESSING_LANGUAGE OR _CMAKE_PROCESSING_LANGUAGE STREQUAL "")
+  message(FATAL_ERROR "Internal error: _CMAKE_PROCESSING_LANGUAGE is not set")
+endif()
+
+# Ubuntu 16.04:
+# * /usr/bin/gcc-ar-5
+# * /usr/bin/gcc-ranlib-5
+string(REGEX MATCH "^([0-9]+)" __version_x
+    "${CMAKE_${_CMAKE_PROCESSING_LANGUAGE}_COMPILER_VERSION}")
+
+string(REGEX MATCH "^([0-9]+\\.[0-9]+)" __version_x_y
+    "${CMAKE_${_CMAKE_PROCESSING_LANGUAGE}_COMPILER_VERSION}")
+
+# Try to find tools in the same directory as GCC itself
+get_filename_component(__gcc_hints "${CMAKE_${_CMAKE_PROCESSING_LANGUAGE}_COMPILER}" DIRECTORY)
+
+# http://manpages.ubuntu.com/manpages/wily/en/man1/gcc-ar.1.html
+find_program(CMAKE_${_CMAKE_PROCESSING_LANGUAGE}_COMPILER_AR NAMES
+    "${_CMAKE_TOOLCHAIN_PREFIX}gcc-ar-${__version_x_y}"
+    "${_CMAKE_TOOLCHAIN_PREFIX}gcc-ar-${__version_x}"
+    "${_CMAKE_TOOLCHAIN_PREFIX}gcc-ar${_CMAKE_COMPILER_SUFFIX}"
+    HINTS ${__gcc_hints}
+    NO_CMAKE_PATH NO_CMAKE_ENVIRONMENT_PATH
+    DOC "A wrapper around 'ar' adding the appropriate '--plugin' option for the GCC compiler"
+)
+mark_as_advanced(CMAKE_${_CMAKE_PROCESSING_LANGUAGE}_COMPILER_AR)
+
+# http://manpages.ubuntu.com/manpages/wily/en/man1/gcc-ranlib.1.html
+find_program(CMAKE_${_CMAKE_PROCESSING_LANGUAGE}_COMPILER_RANLIB NAMES
+    "${_CMAKE_TOOLCHAIN_PREFIX}gcc-ranlib-${__version_x_y}"
+    "${_CMAKE_TOOLCHAIN_PREFIX}gcc-ranlib-${__version_x}"
+    "${_CMAKE_TOOLCHAIN_PREFIX}gcc-ranlib${_CMAKE_COMPILER_SUFFIX}"
+    HINTS ${__gcc_hints}
+    NO_CMAKE_PATH NO_CMAKE_ENVIRONMENT_PATH
+    DOC "A wrapper around 'ranlib' adding the appropriate '--plugin' option for the GCC compiler"
+)
+mark_as_advanced(CMAKE_${_CMAKE_PROCESSING_LANGUAGE}_COMPILER_RANLIB)