[Bug lto/61886] [4.8/4.9/5 Regression] LTO breaks fread with _FORTIFY_SOURCE=2

["hubicka at ucw dot cz" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61886

--- Comment #15 from Jan Hubicka <hubicka at ucw dot cz> ---
> On Mon, Oct 06, 2014 at 11:55:23PM +0200, Jan Hubicka wrote:
> > Hi,
> > I am testing this variant of the patch.
> > For gcc-4.9 branch it may make sense to enable the new patch for LTO only.
> 
> Not printing the inlining backtrace would be IMHO a significant regression.

OK, how do I print it?  I keep the BLOCK of the original expresison, so it is
there.

Honza
> 
> 	Jakub
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From: "davidgkinniburgh at yahoo dot co.uk" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug fortran/63469] New: Automatic reallocation of allocatable scalar length even when substring implicitly specified
Date: Mon, 06 Oct 2014 22:27:00 -0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?idc469

            Bug ID: 63469
           Summary: Automatic reallocation of allocatable scalar length
                    even when substring implicitly specified
           Product: gcc
           Version: 4.9.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: fortran
          Assignee: unassigned at gcc dot gnu.org
          Reporter: davidgkinniburgh at yahoo dot co.uk

CHARACTER(:), ALLOCATABLE :: s

ALLOCATE (character(32) :: s)

s(1:32) = 'string'
print *, 'Length of ', s, ' with substring = ', LEN(s)

s(:) = 'string'
print *, 'Length of ', s, ' with substring = ', LEN(s)

s = 'string'
print *, 'Length of ', s, ' without substring = ', LEN(s)


gfortran (4.9.1 and earlier) gives:

 Length of string                           with substring =           32
 Length of string with substring =            6
 Length of string without substring =            6


IVF (15.0) gives:

 Length of string                           with substring =           32
 Length of string                           with substring =           32
 Length of string without substring =            6

which I think is correct.

It is the implicit definition of both the beginning and the ending of 's' that
seems to do the damage.