From 9851c5ea3410589dadfc43e809fd65ee66b58d28 Mon Sep 17 00:00:00 2001
From: Paul Eggert <eggert@cs.ucla.edu>
Date: Wed, 20 May 2026 08:32:41 -0700
Subject: [PATCH] Shrink STRING_BYTES_MAX slightly
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* src/alloc.c (STRING_BYTES_MAX): Also don’t allow sizes to exceed
PTRDIFF_MAX in internal calculations when calling malloc, as those
are problematic even if the final number of bytes does not exceed
PTRDIFF_MAX.
---
 src/alloc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/alloc.c b/src/alloc.c
index a73e7df1dc7..387b196bbee 100644
--- a/src/alloc.c
+++ b/src/alloc.c
@@ -1501,7 +1501,7 @@ sdata_size (ptrdiff_t n)
    calculating a value to be passed to malloc.  */
 static ptrdiff_t const STRING_BYTES_MAX =
   min (STRING_BYTES_BOUND,
-       ((SIZE_MAX
+       ((min (PTRDIFF_MAX, SIZE_MAX)
 	 - GC_STRING_EXTRA
 	 - offsetof (struct sblock, data)
 	 - SDATA_DATA_OFFSET)