The ability to enable absolutely all warnings (-Wall -Wextra -Wyada-yada-yada), and then selectively disable the one's that are not desired. Rather than the opposite.
Example: g++ -c -Wall-all -Wno-unreachable-code -Wno-long-long -Wno-four-char-constants test.cpp -o test.o -- Summary: -Wall-all to enable all warnings Product: gcc Version: 4.0.1 Status: UNCONFIRMED Severity: enhancement Priority: P3 Component: c++ AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: eljay451 at gmail dot com http://gcc.gnu.org/bugzilla/show_bug.cgi?id=31573