From: Eric Wong <e@80x24.org>
Date: Sun, 24 Oct 2021 00:20:45 +0000 (-0600)
Subject: git: avoid Perl5 internal scratchpad target cache
X-Git-Tag: v1.7.0~64
X-Git-Url: http://www.git.stargrave.org/?p=public-inbox.git;a=commitdiff_plain;h=48af2131c7ef0e7001f99fe3c2dabd1713d3e800

git: avoid Perl5 internal scratchpad target cache

Creating a scalar ref directly off substr() seemed to be causing
the underlying non-ref scalar to end up in Perl's scratchpad.
Assign the substr result to a local variable seems sufficient to
prevent multi-megabyte SVs from lingering indefinitely when a
read-only daemon serves rare, oversized blobs.
---

diff --git a/lib/PublicInbox/Git.pm b/lib/PublicInbox/Git.pm
index 374a3b4d..4078dd5b 100644
--- a/lib/PublicInbox/Git.pm
+++ b/lib/PublicInbox/Git.pm
@@ -158,7 +158,8 @@ sub my_read ($$$) {
 			return; # unrecoverable error
 		}
 	}
-	\substr($$rbuf, 0, $len, '');
+	my $no_pad = substr($$rbuf, 0, $len, '');
+	\$no_pad;
 }
 
 sub my_readline ($$) {