Re: [PATCH] xdiff: implement a zealous diff3
From: Felipe Contreras <hidden>
Date: 2021-06-13 21:25:41
Felipe Contreras wrote:
Jeff King wrote:quoted
Try this: commit=a5170794372cf1325710a3419473c91ec4af53bf for style in merge diff3 zdiff3; do git reset --hard git checkout $commit^1 git -c merge.conflictstyle=$style merge $commit^2 done The first two are fine; the zdiff3 one segfaults within the xmerge.c code.I can reproduct the segfault, and here is a simpler way to reproduce it:
I found the problem, m->chg0 was not initialized in xdl_refine_conflicts. I'm not familiar with the area so I don't know if the following makes sense, but it fixes the crash:
--- a/xdiff/xmerge.c
+++ b/xdiff/xmerge.c@@ -333,7 +333,7 @@ static int xdl_refine_conflicts(xdfenv_t *xe1, xdfenv_t *xe2, xdmerge_t *m, mmfile_t t1, t2; xdfenv_t xe; xdchange_t *xscr, *x; - int i1 = m->i1, i2 = m->i2; + int i0 = m->i0, i1 = m->i1, i2 = m->i2; /* let's handle just the conflicts */ if (m->mode)
@@ -384,6 +384,8 @@ static int xdl_refine_conflicts(xdfenv_t *xe1, xdfenv_t *xe2, xdmerge_t *m, m->next = m2; m = m2; m->mode = 0; + m->i0 = i0; + m->chg0 = 0; m->i1 = xscr->i1 + i1; m->chg1 = xscr->chg1; m->i2 = xscr->i2 + i2;
--
Felipe Contreras