[Bug c++/84401] New: Misleading error message when running out of RAM

[sergey.ignatchenko at ithare dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84401

            Bug ID: 84401
           Summary: Misleading error message when running out of RAM
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: sergey.ignatchenko at ithare dot com
  Target Milestone: ---

Whenever GCC consumes too much RAM (="the box doesn't have enough RAM to
compile whatever-is-necessary-to-compile"), GCC is likely to be sent SIGKILL;
it leads to an error message along the following lines:

g++: internal compiler error: Killed (program cc1plus)
Please submit a full bug report,
with preprocessed source if appropriate.
See <file:///usr/share/doc/gcc-7/README.Bugs> for instructions.

This message is (a) not really helpful for the developer, and (b) causes quite
a few non-bugs to be submitted (such as
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=34882,
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=36665,
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61860 ,
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=30615 ,
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71671 ,
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80434 , 
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=30615, etc. ). 

While there is no _guarantee_ that SIGKILL is caused by lack of RAM, this seems
to be the most likely case by far, so simply adjusting the message (just for
SIGKILL) to the following, would improve quality-of-life both for
devs-using-GCC (who will know what they should do right away), and for GCC devs
(who won't need to deal with non-bug reports):

g++: internal compiler error: Killed (program cc1plus)
This error is often caused by lack of RAM on your computer, PLEASE CHECK THAT
YOU DIDN'T RAN OUT OF RAM FIRST. 
If it is not the case, please submit a full bug report,
with preprocessed source if appropriate.
See <file:///usr/share/doc/gcc-7/README.Bugs> for instructions.