CVS commit: src/external/gpl3/gdb/dist/gdb/nat

["Kamil Rytarowski" <kamil%netbsd.org@localhost>]

Module Name:    src
Committed By:   kamil
Date:           Wed Oct 14 14:02:43 UTC 2020

Modified Files:
        src/external/gpl3/gdb/dist/gdb/nat: fork-inferior.c

Log Message:
Limit the switch_to_thread() calls in startup_inferior()

Do not jump over the threads during the startup unless we encounter
TARGET_WAITKIND_STOPPED with SIGTRAP or TARGET_WAITKIND_EXECD.

Otherwise whenever a startup-with-shell processes signals on the
startup stage, it might indicate to switch to a non-existing
thread or a special-thread number (target lwp=0 on NetBSD means
that a signal was directed to all threads within a process).

This caused a crash with tcsh on NetBSD, where the tcsh shell
runs startup detection of the hostname. This action involves
spwaning a new process through fork.

GDB crashes this way:
$ SHELL=tcsh /usr/bin/gdb echo
(gdb) r
Starting program: /bin/echo
/usr/src/external/gpl3/gdb/lib/libgdb/../../dist/gdb/thread.c:1309:
internal-error: void switch_to_thread(thread_info*):
Assertion `thr != NULL' failed.
A problem internal to GDB has been detected,
further debugging may prove unreliable.

This patch has been submitted upstream for review:

https://sourceware.org/pipermail/gdb-patches/2020-October/172558.html


To generate a diff of this commit:
cvs rdiff -u -r1.1.1.2 -r1.2 \
    src/external/gpl3/gdb/dist/gdb/nat/fork-inferior.c

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.