13092a91 (cocci: refactor common patterns to use xstrdup_or_null(),
2016-10-12) introduced a rule to rewrite this conditional call to
xstrdup(E) and an assignment to variable V:
- if (E)
- V = xstrdup(E);
into an unconditional call to xstrdup_or_null(E) and an assignment
to variable V:
+ V = xstrdup_or_null(E);
which is utterly bogus. The original code may already have an
acceptable value in V and the conditional assignment may be to
improve the value already in V with a copy of a better value E when
(and only when) E is not NULL.
The rewritten construct unconditionally discards the existing value
of V and replaces it with a copy of E, even when E is NULL, which
changes the meaning of the program.
By the way, if it were
-if (E && !V)
- V = xstrdup(E);
+V = xstrdup_or_null(E);
it would probably have been correct. But there is no existing code
that would have been improved by such a rule, so let's just remove
the bogus one without replacing with the more specific one.
Signed-off-by: Junio C Hamano <gitster@xxxxxxxxx>
---
contrib/coccinelle/xstrdup_or_null.cocci | 8 --------
1 file changed, 8 deletions(-)
diff --git a/contrib/coccinelle/xstrdup_or_null.cocci b/contrib/coccinelle/xstrdup_or_null.cocci
index 8e05d1ca4b..9c1d2939b6 100644
--- a/contrib/coccinelle/xstrdup_or_null.cocci
+++ b/contrib/coccinelle/xstrdup_or_null.cocci
@@ -1,11 +1,3 @@
-@@
-expression E;
-expression V;
-@@
-- if (E)
-- V = xstrdup(E);
-+ V = xstrdup_or_null(E);
-
@@
expression E;
@@
--
2.36.0-233-gea8f06b421
