The mcheck wrapper for realloc() unconditionally frees memory and
returns NULL when size is 0. This differs from dlmalloc's default
behaviour which returns a minimum-sized allocation unless
REALLOC_ZERO_BYTES_FREES is defined.
Make the mcheck wrapper respect the same REALLOC_ZERO_BYTES_FREES
setting for consistent behavior with or without mcheck enabled.
Signed-off-by: Simon Glass <simon.glass@canonical.com>
We know or assume that dlmalloc itself works correctly, but there is
still the possibility that the U-Boot integration has bugs.
Add a test suite for the malloc() implementation, covering:
- Basic malloc/free operations
- Edge cases (zero size, NULL pointer handling)
- realloc() in various scenarios
- memalign() with different alignments
- Multiple allocations and fragmentation
- malloc_enable_testing() failure simulation
- Large allocations (1MB, 16MB)
- Full pool allocation (CONFIG_SYS_MALLOC_LEN plus environment size)
- Fill pool test with random sizes
Co-developed-by: Claude <noreply@anthropic.com>
Signed-off-by: Simon Glass <simon.glass@canonical.com>
