From 40c92ff457ece00aced93f2fcc6014b916d9fcf8 Mon Sep 17 00:00:00 2001 From: Phillip Wood Date: Thu, 2 Apr 2026 15:57:44 +0100 Subject: [PATCH] xdiff: reduce the size of array When the myers algorithm is selected the input files are pre-processed to remove any common prefix and suffix and any lines that appear in only one file. This requires a map to be created between the lines that are processed by the myers algorithm and the lines in the original file. That map does not include the common lines at the beginning and end of the files but the array is allocated to be the size of the whole file. Move the allocation into xdl_cleanup_records() where the map is populated and we know how big it needs to be. Signed-off-by: Phillip Wood Signed-off-by: Junio C Hamano --- xdiff/xprepare.c | 11 ++++------- 1 file changed, 4 insertions(+), 7 deletions(-) diff --git a/xdiff/xprepare.c b/xdiff/xprepare.c index 1fd85605ce..862ce827a5 100644 --- a/xdiff/xprepare.c +++ b/xdiff/xprepare.c @@ -171,12 +171,6 @@ static int xdl_prepare_ctx(unsigned int pass, mmfile_t *mf, long narec, xpparam_ if (!XDL_CALLOC_ARRAY(xdf->changed, xdf->nrec + 2)) goto abort; - if ((XDF_DIFF_ALG(xpp->flags) != XDF_PATIENCE_DIFF) && - (XDF_DIFF_ALG(xpp->flags) != XDF_HISTOGRAM_DIFF)) { - if (!XDL_ALLOC_ARRAY(xdf->reference_index, xdf->nrec + 1)) - goto abort; - } - xdf->changed += 1; xdf->nreff = 0; xdf->dstart = 0; @@ -283,7 +277,10 @@ static int xdl_cleanup_records(xdlclassifier_t *cf, xdfile_t *xdf1, xdfile_t *xd * changed[i] should remain false, or become true. */ if (!XDL_CALLOC_ARRAY(action1, len1) || - !XDL_CALLOC_ARRAY(action2, len2)) { + !XDL_CALLOC_ARRAY(action2, len2) || + !XDL_ALLOC_ARRAY(xdf1->reference_index, len1) || + !XDL_ALLOC_ARRAY(xdf2->reference_index, len2)) + { ret = -1; goto cleanup; }