Omit annoying false positives emitted by compiler.

CMakeLists.txt

@@ -247,14 +247,14 @@ if("$ENV{CFLAGS}" STREQUAL "")
 			set(CFLAGS "/Od" CACHE STRING "Default compiler flags.")
 		else()
 			# Turn off all optimizations.
-			set(CFLAGS "-pipe -std=c99 -O0 -fno-omit-frame-pointer -Wno-stringop-overflow -Wno-stringop-overread" CACHE STRING "Default compiler flags.")
+			set(CFLAGS "-pipe -std=c99 -O0 -fno-omit-frame-pointer" CACHE STRING "Default compiler flags.")
 			set(DFLAGS "-ggdb")
 		endif()
 	else()
 		if (MSVC)
 			set(CFLAGS "/O2" CACHE STRING "Default compiler flags.")
 		else()
-			set(CFLAGS "-pipe -std=c99 -O2 -funroll-loops -fomit-frame-pointer -Wno-stringop-overflow -Wno-stringop-overread" CACHE STRING "Default compiler flags.")
+			set(CFLAGS "-pipe -std=c99 -O2 -funroll-loops -fomit-frame-pointer" CACHE STRING "Default compiler flags.")
 		endif()
 	endif()
 else()
@@ -269,6 +269,9 @@ else()
 	set(CFLAGS "$ENV{CFLAGS}" CACHE STRING "User-chosen compiler flags.")
 endif()
 
+# Remove annoying flags when compiler cannot compute buffer sizes.
+set(CFLAGS "${CFLAGS} -Wno-stringop-overflow -Wno-stringop-overread")
+
 if(AUSAN)
 	set(DFLAGS "${DFLAGS} -ggdb -fsanitize=address -fsanitize=undefined")
 endif()