[PR build/24886] disable glibc mcheck support
authorFrank Ch. Eigler <fche@redhat.com>
Tue, 6 Aug 2019 15:23:48 +0000 (11:23 -0400)
committerFrank Ch. Eigler <fche@redhat.com>
Tue, 6 Aug 2019 19:09:53 +0000 (15:09 -0400)
commit404f29021abaef86a341663444fb069eb1f0282a
tree76a3409f363d27b2c0fcceaaea2dcf2a86f7e5e6
parent046bebe1c0a367687bd693eb4594fcdcba0b8f7e
[PR build/24886] disable glibc mcheck support

This patch drops gdb's configury support for glibc's mcheck function.
It has been observed to cause false abort()s, because it is
thread-unsafe yet interposes every malloc/free operation.  So if any
library transitively used by gdb also uses threads, then these
functions can easily corrupt their own checking data.  These days, gcc
ASAN and valgrind provide high quality checking, and mcheck is
apparently itself being slowly deprecated.

So, let's stop linking to it.  Attached patch drops the
autoconf/Makefile machinery for both gdb and gdbserver.  No
testsuite-visible impact.  IMHO not worth mentioning in NEWS.

See also: https://sourceware.org/bugzilla/show_bug.cgi?id=9939

gdb/ChangeLog

        PR build/24886
        * configure.ac: Drop enable-libmcheck support.
        * configure, config.in: Rebuild.
        * libmcheck.m4: Remove.
        * acinclude.m4: Don't include it.
        * Makefile.in: Don't distribute it.
        * top.c (print_gdb_configuration): Don't mention it.

gdb/gdbserver/ChangeLog

        PR build/24886
        * configure.ac: Drop enable-libmcheck support.
        * configure, config.in: Rebuild.
        * acinclude.m4: Don't include it.
13 files changed:
gdb/ChangeLog
gdb/Makefile.in
gdb/acinclude.m4
gdb/config.in
gdb/configure
gdb/configure.ac
gdb/gdbserver/ChangeLog
gdb/gdbserver/acinclude.m4
gdb/gdbserver/config.in
gdb/gdbserver/configure
gdb/gdbserver/configure.ac
gdb/libmcheck.m4 [deleted file]
gdb/top.c