Quash a whole bunch of warnings

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@145624 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/buildit b/lib/buildit
index b307806..0b1f6e5 100755
--- a/lib/buildit
+++ b/lib/buildit
@@ -35,7 +35,9 @@
   RC_ProjectSourceVersion=1
 fi
 
-EXTRA_FLAGS="-std=c++0x"
+EXTRA_FLAGS="-std=c++0x -fstrict-aliasing -Wall -Wextra -Wshadow -Wconversion \
+             -Wnewline-eof -Wpadded -Wmissing-prototypes -Wstrict-aliasing=2 \
+             -Wstrict-overflow=4"
 
 case $TRIPLE in
   *-apple-*)