pcre: check for pcre_free_study, fall back to pcre_free if it unavailable

configure.ac

@@ -469,6 +469,14 @@
         echo
     fi
 
+    TMPCFLAGS="${CFLAGS}"
+    CFLAGS="-O0 -g -Werror -Wall"
+    AC_TRY_COMPILE([ #include <pcre.h> ],
+        [ pcre_extra *extra = NULL; pcre_free_study(extra); ],
+        [ AC_DEFINE([HAVE_PCRE_FREE_STUDY], [1], [Pcre pcre_free_study supported])], [:]
+    )
+    CFLAGS="${TMPCFLAGS}"
+
     #enable support for PCRE-jit available since pcre-8.20
     AC_MSG_CHECKING(for PCRE JIT support)
     AC_TRY_COMPILE([ #include <pcre.h> ],

src/suricata-common.h

@@ -270,6 +270,10 @@
 #endif
 #endif
 
+#ifndef HAVE_PCRE_FREE_STUDY
+#define pcre_free_study pcre_free
+#endif
+
 typedef enum PacketProfileDetectId_ {
     PROF_DETECT_MPM,
     PROF_DETECT_MPM_PACKET,         /* PKT MPM */