gitlab-ci, meson: Enable colored Clang output

This makes easier to spot warnings.

.gitlab-ci.yml

@@ -102,6 +102,8 @@ variables:
   # CI-wide Debian variables
   ARTIFACTS_SUFFIX: "-x64"
   GIMP_PREFIX: "${CI_PROJECT_DIR}/_install${ARTIFACTS_SUFFIX}"
+  # Enable colorful output when supported (e.g. ninja, cppcheck)
+  CLICOLOR_FORCE: "1"
 
 
 stages:

meson.build

@@ -289,10 +289,14 @@ if platform_windows and cc.get_id() == 'gcc'
   compiler_args += msvc_compat_args
 endif
 
-# Optimize DWARF symbols to Dr. Mingw
-# https://github.com/jrfonseca/drmingw/issues/42
+
 if platform_windows and cc.get_id() == 'clang'
+  # Optimize DWARF symbols to Dr. Mingw
+  # https://github.com/jrfonseca/drmingw/issues/42
   compiler_args += '-gdwarf-aranges'
+  # Workaround to get colored output
+  # https://github.com/msys2/MINGW-packages/issues/2988
+  compiler_args += '-fansi-escape-codes'
 endif
 
 # Generate .pdb (CodeView) debug symbols (makes possible to debug with DIA SDK)