commit f144981490bd2ab13189d85902ca74beecb307e4

Author: DJ Delorie <dj@redhat.com>

Date:   Wed Oct 30 18:03:14 2019 -0400

    Base max_fast on alignment, not width, of bins (Bug 24903)

    set_max_fast sets the "impossibly small" value based on,

    eventually, MALLOC_ALIGNMENT.  The comparisons for the smallest

    chunk used is, eventually, MIN_CHUNK_SIZE.  Note that i386

    is the only platform where these are the same, so a smallest

    chunk *would* be put in a no-fastbins fastbin.

    This change calculates the "impossibly small" value

    based on MIN_CHUNK_SIZE instead, so that we can know it will

    always be impossibly small.

    (cherry picked from commit ff12e0fb91b9072800f031cb21fb2651ee7b6251)

diff --git a/malloc/malloc.c b/malloc/malloc.c

index 9756ed0a0d28c5f6..90825b2aaed53761 100644

--- a/malloc/malloc.c

+++ b/malloc/malloc.c

@@ -1635,7 +1635,7 @@ static INTERNAL_SIZE_T global_max_fast;

 #define set_max_fast(s) \

   global_max_fast = (((s) == 0)						      \

-                     ? SMALLBIN_WIDTH : ((s + SIZE_SZ) & ~MALLOC_ALIGN_MASK))

+                     ? MIN_CHUNK_SIZE / 2 : ((s + SIZE_SZ) & ~MALLOC_ALIGN_MASK))

 static inline INTERNAL_SIZE_T

 get_max_fast (void)