[PATCH 3/3] Avoid GDB SIGTTOU on catch exec + set follow-exec-mode new (PR 23368)

[Simon Marchi]

On 2018-10-24 05:41, Andreas Schwab wrote:
> That's still broken:
> 
> $ ./gdb gdb
> GNU gdb (GDB) 8.2.50.20181024-git
> Copyright (C) 2018 Free Software Foundation, Inc.
> License GPLv3+: GNU GPL version 3 or later 
> <http://gnu.org/licenses/gpl.html>
> 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 "ia64-unknown-linux-gnu".
> Type "show configuration" for configuration details.
> For bug reporting instructions, please see:
> <http://www.gnu.org/software/gdb/bugs/>.
> Find the GDB manual and other documentation resources online at:
>     <http://www.gnu.org/software/gdb/documentation/>.
> 
> For help, type "help".
> Type "apropos word" to search for commands related to "word"...
> Reading symbols from gdb...
> Setting up the environment for debugging gdb.
> During symbol reading: unsupported tag: 'DW_TAG_unspecified_type'
> Breakpoint 1 at 0x400000000018fc00: file ../../gdb/common/errors.c, 
> line 51.
> During symbol reading: Member function "~_Sp_counted_base" (offset
> 0x517e90) is virtual but the vtable offset is not specified
> During symbol reading: cannot get low and high bounds for subprogram
> DIE at 0x5201ee
> During symbol reading: missing name for subprogram DIE at 0x5246c8
> During symbol reading: Child DIE 0x52f12a and its abstract origin
> 0x52cafc have different parents
> During symbol reading: Multiple children of DIE 0x53138e refer to DIE
> 0x52be3c as their abstract origin
> During symbol reading: DW_AT_call_target target DIE has invalid low
> pc, for referencing DIE 0x53a7e0 [in module
> /usr/local/gcc/gdb/Build/gdb/gdb]
> Breakpoint 2 at 0x4000000000150ac0: file ../../gdb/cli/cli-cmds.c, line 
> 197.
> (top-gdb) r
> Starting program: /usr/local/gcc/gdb/Build/gdb/gdb
> During symbol reading: .debug_line section has line program sequence
> without an end
> 
> [1]+  Stopped                 ./gdb gdb
> $ fg
> ./gdb gdb
> Failed to read a valid object file image from memory.
> During symbol reading: .debug_line section has line program sequence
> without an end
> During symbol reading: .debug_line section has line program sequence
> without an end
> [Detaching after vfork from child process 11772]
> GNU gdb (GDB) 8.2.50.20181024-git
> Copyright (C) 2018 Free Software Foundation, Inc.
> License GPLv3+: GNU GPL version 3 or later 
> <http://gnu.org/licenses/gpl.html>
> 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 "ia64-unknown-linux-gnu".
> Type "show configuration" for configuration details.
> For bug reporting instructions, please see:
> <http://www.gnu.org/software/gdb/bugs/>.
> Find the GDB manual and other documentation resources online at:
>     <http://www.gnu.org/software/gdb/documentation/>.
> 
> For help, type "help".
> Type "apropos word" to search for commands related to "word".
> 
> Andreas.

That looks like a different case of SIGTTOU, same symptom but different 
root cause.  I didn't claim I fixed all of them :)

Simon