undefined reference to `free'

Index: configure.ac
--- configure.ac.orig
+++ configure.ac
@@ -44,8 +44,6 @@ AC_PROG_AWK
 
 AX_CXX_COMPILE_STDCXX(11, noext)
 
-CODEBLOCKS_CHECK_LINK_FLAG([-Wl,--no-undefined],[LDFLAGS="-Wl,--no-undefined $LDFLAGS"])
-
 CODEBLOCKS_SETUP_FOR_TARGET
 
 dnl Checks for header files.
