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[PATCH 1/2] tree-diff: fix leak when not HAVE_ALLOCA

From
Carlo Marcelo Arenas Belón <carenas@gmail.com>
Date
Sep 16, 2021, 02:37 UTC
Message-ID
<20210916023706.55760-2-carenas@gmail.com>
In-Reply-To
<20210916023706.55760-1-carenas@gmail.com>

b8ba412bf7 (tree-diff: avoid alloca for large allocations, 2016-06-07) adds a way to route some bigger allocations out of the stack and free them through the addition of two conveniently named macros, but leaves the calls to free the xalloca part, which could be also in the heap, if the system doesn't HAVE_ALLOCA (ex: macOS).

Add the missing free call, and while at it, change the expression to match in both macros for easy of readability.

This avoids a leak reported by LSAN as while running t0000 but that wouldn't fail the test (which will be fixed next) :

  SUMMARY: LeakSanitizer: 1034 byte(s) leaked in 15 allocation(s).
Signed-off-by: Carlo Marcelo Arenas Belón <carenas@gmail.com>
---
 tree-diff.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/tree-diff.c b/tree-diff.c
index 1572615bd9..437c98a70e 100644
--- a/tree-diff.c
+++ b/tree-diff.c
@@ -21,7 +21,9 @@
 		ALLOC_ARRAY((x), nr); \
 } while(0)
 #define FAST_ARRAY_FREE(x, nr) do { \
-	if ((nr) > 2) \
+	if ((nr) <= 2) \
+		xalloca_free((x)); \
+	else \
 		free((x)); \
 } while(0)
 
-- 
2.33.0.481.g26d3bed244
Previous: Carlo Marcelo Arenas BelónNext: Taylor Blau
Message 2 of 15 in “t0000: truly leak free”
  1. 0/2 t0000: truly leak freeCarlo Marcelo Arenas Belón, Sep 16, 2021
  2. 1/2 tree-diff: fix leak when not HAVE_ALLOCACarlo Marcelo Arenas Belón, Sep 16, 2021
  3. Taylor BlauSep 16, 2021
  4. Junio C HamanoSep 16, 2021
  5. 2/2 t0000: avoid masking git exit value through pipesCarlo Marcelo Arenas Belón, Sep 16, 2021
  6. Taylor BlauSep 16, 2021
  7. Junio C HamanoSep 16, 2021
  8. Taylor BlauSep 16, 2021
  9. Junio C HamanoSep 16, 2021
  10. Ævar Arnfjörð BjarmasonSep 16, 2021
  11. 0/2 reroll for cb/plug-leaks-in-alloca-emu-usersCarlo Marcelo Arenas Belón, Sep 16, 2021
  12. 1/2 tree-diff: fix leak when not HAVE_ALLOCA_HCarlo Marcelo Arenas Belón, Sep 16, 2021
  13. Jeff KingSep 16, 2021
  14. 2/2 t0000: avoid masking git exit value through pipesCarlo Marcelo Arenas Belón, Sep 16, 2021
  15. Taylor BlauSep 16, 2021

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