(nuttx) branch master updated: sim/heap: malloc returns a valid pointer when allocating 0 bytes.

[ligd]

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ligd pushed a commit to branch master
in repository https://gitbox.apache.org/repos/asf/nuttx.git


The following commit(s) were added to refs/heads/master by this push:
     new d01bbaecc1 sim/heap: malloc returns a valid pointer when allocating 0 
bytes.
d01bbaecc1 is described below

commit d01bbaecc1063fa98af5737cb4aeba5b20f2d454
Author: yinshengkai <yinsheng...@xiaomi.com>
AuthorDate: Mon Nov 13 15:35:47 2023 +0800

    sim/heap: malloc returns a valid pointer when allocating 0 bytes.
    
    The default heap management in nuttx returns a valid memory address when 
malloc(0).
    In sim_heap, malloc(0) returns NULL, aligning the behavior of sim_heap with 
mm_heap
    
    The man manual describes malloc as follows:
    https://man7.org/linux/man-pages/man3/malloc.3.html
    
    The malloc() function allocates size bytes and returns a pointer
    to the allocated memory.  The memory is not initialized.  If size
    is 0, then malloc() returns a unique pointer value that can later
    be successfully passed to free().  (See "Nonportable behavior"
    for portability issues.)
    
    Signed-off-by: yinshengkai <yinsheng...@xiaomi.com>
---
 arch/sim/src/sim/sim_heap.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/arch/sim/src/sim/sim_heap.c b/arch/sim/src/sim/sim_heap.c
index e95b559ff1..7b95441f7a 100644
--- a/arch/sim/src/sim/sim_heap.c
+++ b/arch/sim/src/sim/sim_heap.c
@@ -375,8 +375,7 @@ void *mm_realloc(struct mm_heap_s *heap, void *oldmem,
 
   if (size == 0)
     {
-      mm_free(heap, oldmem);
-      return NULL;
+      size = 1;
     }
 
   oldsize = host_mallocsize(oldmem);