[Emacs-diffs] master 945a762: Fix emacs_re_safe_alloca calculation

[Paul Eggert]

branch: master
commit 945a7622326f7d93dd318f01d54f6bf23e0021cf
Author: Paul Eggert <address@hidden>
Commit: Paul Eggert <address@hidden>

    Fix emacs_re_safe_alloca calculation
    
    Problem and draft fix noted by Eli Zaretskii in:
    https://lists.gnu.org/r/emacs-devel/2018-10/msg00022.html
    * src/emacs.c (main): Fix arithmetic used in calculation
    of emacs_re_safe_alloca.
---
 src/emacs.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/src/emacs.c b/src/emacs.c
index b1c96d1..ddaaf3f 100644
--- a/src/emacs.c
+++ b/src/emacs.c
@@ -888,11 +888,11 @@ main (int argc, char **argv)
                lim = newlim;
            }
        }
-      /* If the stack is big enough, let regex-emacs.c more of it before
-         falling back to heap allocation.  */
-      emacs_re_safe_alloca = max
-        (min (lim - extra, SIZE_MAX) * (min_ratio / ratio),
-         MAX_ALLOCA);
+      /* If the stack is big enough, let regex-emacs.c use more of it
+        before falling back to heap allocation.  */
+      ptrdiff_t max_failures
+       = min (lim - extra, min (PTRDIFF_MAX, SIZE_MAX)) / ratio;
+      emacs_re_safe_alloca = max (max_failures * min_ratio, MAX_ALLOCA);
     }
 #endif /* HAVE_SETRLIMIT and RLIMIT_STACK and not CYGWIN */