diff --git a/ext/ruby_prof/extconf.rb b/ext/ruby_prof/extconf.rb
index 6dd5bf7d..a4d2847c 100644
--- a/ext/ruby_prof/extconf.rb
+++ b/ext/ruby_prof/extconf.rb
@@ -6,4 +6,7 @@
 # We want to intermix declarations and code (ie, don't define all variables at the top of the method)
 $CFLAGS += ' -std=c99'
 
+# And since we are using C99 we want to disable Ruby sending these warnings to gcc
+CONFIG['warnflags'].gsub!('-Wdeclaration-after-statement', '')
+
 create_makefile("ruby_prof")