gerbil: update to 0.18.1.

srcpkgs/gerbil/patches/gxtags.patch

@@ -0,0 +1,11 @@
+--- a/src/tools/gxtags.ss
++++ b/src/tools/gxtags.ss
+@@ -261,7 +261,7 @@
+ 
+ (def (source-location-line locat)
+   (if (##locat? locat)
+-    (let (filepos (##position->filepos (##locat-position locat)))
++    (let (filepos (##position->filepos (##locat-start-position locat)))
+       (fx1+ (##filepos-line filepos)))
+     1))
+ 

srcpkgs/gerbil/template

@@ -1,7 +1,8 @@
 # Template file for 'gerbil'
 pkgname=gerbil
-version=0.18
-revision=2
+version=0.18.1
+revision=1
+_gitrev="23c30a6062cd7e63f9d85300ce01585bb9035d2d"
 build_style="configure"
 configure_args="--prefix=/usr/lib/gerbil --enable-march="
 hostmakedepends="git tar"
@@ -12,7 +13,6 @@ short_desc="Opinionated dialect of Scheme designed for Systems Programming"
 maintainer="Leah Neukirchen <leah@vuxu.org>"
 license="LGPL-2.1-or-later, Apache-2.0"
 homepage="https://cons.io/"
-_gitrev="f5c3cce810b56f6823c5badc8723a9dbbb9cb804"
 nocross="yes"
 
 do_fetch() {