Merge branch 'enhanced_viewport_overlay' into jgrpp

Further fixes for viewport lines/marker for multiplayer clients.

# Conflicts:
#	src/lang/russian.txt

config.lib

@@ -1433,11 +1433,14 @@ make_compiler_cflags() {
 			flags="$flags -fno-tree-vrp"
 		fi
 
-		if [ $cc_version -ge 407 ]; then
+		if [ $cc_version -eq 407 ]; then
 			# Disable -Wnarrowing which gives many warnings, such as:
 			# warning: narrowing conversion of '...' from 'unsigned int' to 'int' inside { } [-Wnarrowing]
 			# They are valid according to the C++ standard, but useless.
 			cxxflags="$cxxflags -Wno-narrowing"
+		fi
+
+		if [ $cc_version -ge 407 ]; then
 			# Disable bogus 'attempt to free a non-heap object' warning
 			flags="$flags -Wno-free-nonheap-object"
 		else