[Bug libstdc++/86130] Expect SIGSEGV but program just silently exits

[Bug libstdc++/86130] Expect SIGSEGV but program just silently exits

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86130

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
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                 CC|                            |mimomorin at gmail dot com

--- Comment #17 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
*** Bug 109891 has been marked as a duplicate of this bug. ***

[Bug libstdc++/86130] Expect SIGSEGV but program just silently exits

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86130

Jonathan Wakely <redi at gcc dot gnu.org> changed:

           What    |Removed                     |Added
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             Status|UNCONFIRMED                 |NEW
     Ever confirmed|0                           |1
   Last reconfirmed|                            |2023-07-10

--- Comment #18 from Jonathan Wakely <redi at gcc dot gnu.org> ---
(In reply to Jonathan Wakely from comment #13)
> I think there would need to be a period of deprecation and an optional
> assertion enabled by _GLIBCXX_ASSERTIONS before we can do that (assuming we
> want to).

As I said in the PR 109891 dup, _GLIBCXX_DEBUG_PEDANTIC exists for precisely
this kind of case:
https://gcc.gnu.org/onlinedocs/libstdc++/manual/debug_mode_semantics.html

So let's add that for now.

[Bug libstdc++/86130] Expect SIGSEGV but program just silently exits

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86130

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |llvm at rifkin dot dev

--- Comment #19 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
*** Bug 111729 has been marked as a duplicate of this bug. ***

[Bug libstdc++/86130] Expect SIGSEGV but program just silently exits

[llvm at rifkin dot dev]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86130

--- Comment #20 from Jeremy R. <llvm at rifkin dot dev> ---
Silently ruining the behavior of the rest of a program and leaving the
programmer to pull their hair out over what on earth is happening seems very
un-ideal behavior.

This is a very easy mistake to make and the current behavior makes tracking
down that mistake exceedingly difficult.

I do recognize the concerns here about existing programs and crashing being
arguably less friendly, but something should be done here. 

Libc++ and msvc's stl both segfault and there's some value in making the
behavior here consistent.

(In reply to Jonathan Wakely from comment #13)
> I'm not suggesting we should print "(null)", that would be crazy
Maybe, but it's also a nice middle ground between silently corrupting the
stream and crashing the program.

Throwing an exception, even only in debug, also seems reasonable as existing
programs may be able to recover from the exception without crashing.

[Bug libstdc++/86130] Expect SIGSEGV but program just silently exits

[llvm at rifkin dot dev]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86130

--- Comment #21 from Jeremy R. <llvm at rifkin dot dev> ---
Another option might be just do nothing and don't set the badbit, just pretend
it's an empty string. This shouldn't break existing programs and would at least
be something a programmer could more easily track down.