diff --git a/compiler-rt/lib/scudo/standalone/CMakeLists.txt b/compiler-rt/lib/scudo/standalone/CMakeLists.txt
--- a/compiler-rt/lib/scudo/standalone/CMakeLists.txt
+++ b/compiler-rt/lib/scudo/standalone/CMakeLists.txt
@@ -7,6 +7,8 @@
 list(APPEND SCUDO_CFLAGS
   -Werror=conversion
   -Wall
+  -Wextra
+  -pedantic
   -g
   -nostdinc++)