$ gdb /usr/local/apache/bin/httpd GNU gdb (GDB) Red Hat Enterprise Linux (7.2-75.el6) Copyright (C) 2010 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. Type "show copying" and "show warranty" for details. This GDB was configured as "x86_64-redhat-linux-gnu". For bug reporting instructions, please see: ... Reading symbols from /usr/local/apache/bin/httpd...done. (gdb) r -X -DSSL Starting program: /usr/local/apache/bin/httpd -X -DSSL [Thread debugging using libthread_db enabled] Program received signal SIGSEGV, Segmentation fault. __strcmp_sse2 () at ../sysdeps/x86_64/strcmp.S:213 213 movlpd (%rdi), %xmm1 (gdb) bt #0 __strcmp_sse2 () at ../sysdeps/x86_64/strcmp.S:213 #1 0x0000000000469e26 in ap_add_cgi_vars (r=0x807b58) at util_script.c:360 #2 0x000000000048b58b in includes_filter (f=0x80b260, b=0x80b4c0) at mod_include.c:3887 #3 0x0000000000440ad2 in ap_pass_brigade (next=0x80b260, bb=0x80b4c0) at util_filter.c:590 #4 0x0000000000450303 in default_handler (r=0x807b58) at core.c:4385 #5 0x000000000045e5c3 in ap_run_handler (r=0x807b58) at config.c:170 #6 0x000000000045f010 in ap_invoke_handler (r=0x807b58) at config.c:433 #7 0x0000000000498a6d in ap_internal_redirect (new_uri=0x7b58e0 "/400.shtml", r=0x806570) at http_request.c:648 #8 0x000000000049777b in ap_die (type=400, r=0x806570) at http_request.c:202 #9 0x0000000000444ba9 in ap_read_request (conn=0x7fc710) at protocol.c:974 #10 0x0000000000494121 in ap_process_http_sync_connection (c=0x7fc710) at http_core.c:181 #11 0x000000000049417f in ap_process_http_connection (c=0x7fc710) at http_core.c:231 #12 0x000000000046c531 in ap_run_process_connection (c=0x7fc710) at connection.c:41 #13 0x000000000046ca37 in ap_process_connection (c=0x7fc710, csd=0x7fc520) at connection.c:213 #14 0x0000000000506b96 in child_main (child_num_arg=0) at prefork.c:704 #15 0x0000000000506cad in make_child (s=0x797948, slot=0) at prefork.c:746 #16 0x0000000000507245 in prefork_run (_pconf=0x765138, plog=0x7a0d08, s=0x797948) at prefork.c:956 #17 0x000000000043dcb0 in ap_run_mpm (pconf=0x765138, plog=0x7a0d08, s=0x797948) at mpm_common.c:96 #18 0x0000000000435fa6 in main (argc=3, argv=0x7fffffffe1a8) at main.c:777