[Bug fortran/79492] LHS reallocation, intrinsic function RHS, and -fcheck=all

[kargl at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79492

kargl at gcc dot gnu.org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Priority|P3                          |P4
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2017-02-13
                 CC|                            |kargl at gcc dot gnu.org,
                   |                            |pault at gcc dot gnu.org
            Summary|odd behaviour triggered on  |LHS reallocation, intrinsic
                   |applying log function       |function RHS, and
                   |                            |-fcheck=all
     Ever confirmed|0                           |1
      Known to fail|                            |6.3.1, 7.0.1

--- Comment #1 from kargl at gcc dot gnu.org ---
This bug appears to date back to 

troutmask:sgk[224] svn log -r 167220 | more
------------------------------------------------------------------------
r167220 | pault | 2010-11-28 05:47:26 -0800 (Sun, 28 Nov 2010) | 51 lines

2010-11-28  Paul Thomas  <pault@gcc.gnu.org>

The suggested back is

Index: trans-expr.c
===================================================================
--- trans-expr.c        (revision 245254)
+++ trans-expr.c        (working copy)
@@ -9811,7 +9811,7 @@ gfc_trans_assignment_1 (gfc_expr * expr1
   /* Walk the lhs.  */
   lss = gfc_walk_expr (expr1);
   if (gfc_is_reallocatable_lhs (expr1)
-       && !(expr2->expr_type == EXPR_FUNCTION
+       && (expr2->expr_type == EXPR_FUNCTION
             && expr2->value.function.isym != NULL))
     lss->is_alloc_lhs = 1;
   rss = NULL;

In other words, the 2nd part of the if conditional looks to
be meant to disable LHS reallocation if the intrinsic procedure
is NULL().  Paul was that your intention five years ago?