Avoid unnecessary "if-before-free" tests.
This change removes all obvious useless if-before-free tests.
E.g., it replaces code like this:
if (some_expression)
free (some_expression);
with the now-equivalent:
free (some_expression);
It is equivalent not just because POSIX has required free(NULL)
to work for a long time, but simply because it has worked for
so long that no reasonable porting target fails the test.
Here's some evidence from nearly 1.5 years ago:
http://www.winehq.org/pipermail/wine-patches/2006-October/031544.html
FYI, the change below was prepared by running the following:
git ls-files -z | xargs -0 \
perl -0x3b -pi -e \
's/\bif\s*\(\s*(\S+?)(?:\s*!=\s*NULL)?\s*\)\s+(free\s*\(\s*\1\s*\))/$2/s'
Note however, that it doesn't handle brace-enclosed blocks like
"if (x) { free (x); }". But that's ok, since there were none like
that in git sources.
Beware: if you do use the above snippet, note that it can
produce syntactically invalid C code. That happens when the
affected "if"-statement has a matching "else".
E.g., it would transform this
if (x)
free (x);
else
foo ();
into this:
free (x);
else
foo ();
There were none of those here, either.
If you're interested in automating detection of the useless
tests, you might like the useless-if-before-free script in gnulib:
[it *does* detect brace-enclosed free statements, and has a --name=S
option to make it detect free-like functions with different names]
http://git.sv.gnu.org/gitweb/?p=gnulib.git;a=blob;f=build-aux/useless-if-before-free
Addendum:
Remove one more (in imap-send.c), spotted by Jean-Luc Herren <jlh@gmx.ch>.
Signed-off-by: Jim Meyering <meyering@redhat.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/diff.c b/diff.c
index 699b21f..f08e663 100644
--- a/diff.c
+++ b/diff.c
@@ -118,8 +118,7 @@
pp->next = funcname_pattern_list;
funcname_pattern_list = pp;
}
- if (pp->pattern)
- free(pp->pattern);
+ free(pp->pattern);
pp->pattern = xstrdup(value);
return 0;
}
@@ -492,10 +491,8 @@
ecbdata->diff_words->plus.text.size)
diff_words_show(ecbdata->diff_words);
- if (ecbdata->diff_words->minus.text.ptr)
- free (ecbdata->diff_words->minus.text.ptr);
- if (ecbdata->diff_words->plus.text.ptr)
- free (ecbdata->diff_words->plus.text.ptr);
+ free (ecbdata->diff_words->minus.text.ptr);
+ free (ecbdata->diff_words->plus.text.ptr);
free(ecbdata->diff_words);
ecbdata->diff_words = NULL;
}
