From bdb13d2c7cf22236d7fb9d4f0a0fa46dd08d128a Mon Sep 17 00:00:00 2001
From: Rui Ueyama <ruiu@google.com>
Date: Wed, 11 Jan 2017 22:55:35 +0000
Subject: [PATCH] Add -Wl,-color-diagnostics if a linker supports the option.

Differential Revision: https://reviews.llvm.org/D28046

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@291719 91177308-0d34-0410-b5e6-96231b3b80d8
---
 cmake/modules/CheckLinkerFlag.cmake   | 8 ++++++++
 cmake/modules/HandleLLVMOptions.cmake | 8 ++++++++
 2 files changed, 16 insertions(+)
 create mode 100644 cmake/modules/CheckLinkerFlag.cmake

diff --git a/cmake/modules/CheckLinkerFlag.cmake b/cmake/modules/CheckLinkerFlag.cmake
new file mode 100644
index 00000000000..e96d35e7721
--- /dev/null
+++ b/cmake/modules/CheckLinkerFlag.cmake
@@ -0,0 +1,8 @@
+include(CheckCXXCompilerFlag)
+
+function(check_linker_flag flag out_var)
+  set(OLD_CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS}")
+  set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} ${flag}")
+  check_cxx_compiler_flag("" ${out_var})
+  set(CMAKE_REQUIRED_FLAGS ${OLD_CMAKE_REQUIRED_FLAGS})
+endfunction()
diff --git a/cmake/modules/HandleLLVMOptions.cmake b/cmake/modules/HandleLLVMOptions.cmake
index 89d90befc81..4ce7f57403c 100644
--- a/cmake/modules/HandleLLVMOptions.cmake
+++ b/cmake/modules/HandleLLVMOptions.cmake
@@ -597,6 +597,14 @@ if (UNIX AND
   append("-fcolor-diagnostics" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
 endif()
 
+# lld doesn't print colored diagnostics when invoked from Ninja
+if (UNIX AND CMAKE_GENERATOR STREQUAL "Ninja")
+  include(CheckLinkerFlag)
+  check_linker_flag("-Wl,-color-diagnostics" LINKER_SUPPORTS_COLOR_DIAGNOSTICS)
+  append_if(LINKER_SUPPORTS_COLOR_DIAGNOSTICS "-Wl,-color-diagnostics"
+    CMAKE_EXE_LINKER_FLAGS CMAKE_MODULE_LINKER_FLAGS CMAKE_SHARED_LINKER_FLAGS)
+endif()
+
 # Add flags for add_dead_strip().
 # FIXME: With MSVS, consider compiling with /Gy and linking with /OPT:REF?
 # But MinSizeRel seems to add that automatically, so maybe disable these
-- 
2.50.1