redirect stderr to /dev/null for clang-tidy

Author: igagis

src/prorab.mk

@@ -259,7 +259,8 @@ ifneq ($(prorab_is_included),true)
     endif
 
     # define predefined lint command for clang-tidy
-    prorab_lint_cmd_clang_tidy = clang-tidy --quiet $$< -- $(this_cppflags) $$(if $$(patsubst %.c,,$$<),$(this_cxxflags),$(this_cflags))
+    # NOTE: stderr is redirected to /dev/null because clang-tidy prints non-relevant warning messages to stderr which are to be ignored
+    prorab_lint_cmd_clang_tidy = clang-tidy --quiet $$< -- $(this_cppflags) $$(if $$(patsubst %.c,,$$<),$(this_cxxflags),$(this_cflags)) 2>/dev/null
 
     # set number of parallel jobs. In case number of jobs is given from the command line via '-j' or '--jobs' option
     # then this setting will be ignored by GNU make