diff --git a/configure.ac b/configure.ac
index be657b0..fca48e0 100644
--- a/configure.ac
+++ b/configure.ac
@@ -139,20 +139,17 @@ CC="$PTHREAD_CC"
 AC_ARG_ENABLE(compiler-flags, AS_HELP_STRING([--disable-compiler-flags],[Disable *all* additional compiler flags. [no]]))
 
 AS_IF([test x$enable_compiler_flags != xno], [
-  CFLAGS="$CFLAGS -Wall -Wextra -Wno-unused-parameter -std=gnu99 -pipe -g"
-  CXXFLAGS="$CXXFLAGS -Wall -Wextra -Wno-unused-parameter -fno-strict-aliasing -pipe -g"
+  CFLAGS="$CFLAGS -Wall -Wextra -Wno-unused-parameter"
+  CXXFLAGS="$CXXFLAGS -Wall -Wextra -Wno-unused-parameter"
+  AC_C_FLAG([-std=gnu99])
   AC_CXX_FLAG([-std=c++11])
-  AC_CXX_FLAG([-Wno-c++11-narrowing])
   AC_C_FLAG([-Wno-unused-local-typedefs])
   AC_CXX_FLAG([-Wno-unused-local-typedefs])
 
   # -O* messes with debugging.
   AS_IF([test x$enable_debug = xyes], [
-    CFLAGS="$CFLAGS -O0"
-    CXXFLAGS="$CXXFLAGS -O0"
-  ], [
-    CFLAGS="$CFLAGS -O3"
-    CXXFLAGS="$CXXFLAGS -O3"
+    CFLAGS="$CFLAGS -O0 -g"
+    CXXFLAGS="$CXXFLAGS -O0 -g"
   ])
 ])