ncurses: use patch from Arch for fixing leaked LDFLAGS in .pc files

ncurses/PKGBUILD

@@ -3,20 +3,26 @@
 pkgbase=ncurses
 pkgname=('ncurses' 'ncurses-devel')
 pkgver=6.3
-pkgrel=1
+pkgrel=2
 pkgdesc="System V Release 4.0 curses emulation library"
 arch=('i686' 'x86_64')
 url="https://www.gnu.org/software/ncurses/"
 license=('MIT')
 makedepends=('autotools' 'gcc')
 source=(#"${pkgbase}-${pkgver}.tar.gz"::"https://invisible-mirror.net/archives/ncurses/current/${pkgbase}-${_basever}-${_date}.tgz"
-        https://ftp.gnu.org/pub/gnu/ncurses/ncurses-${pkgver}.tar.gz{,.sig})
+        https://ftp.gnu.org/pub/gnu/ncurses/ncurses-${pkgver}.tar.gz{,.sig}
+        "ncurses-6.3-pkgconfig.patch")
 sha256sums=('97fc51ac2b085d4cde31ef4d2c3122c21abc217e9090a43a30fc5ec21684e059'
-            'SKIP')
+            'SKIP'
+            'b8544a607dfbeffaba2b087f03b57ed1fa81286afca25df65f61b04b5f3b3738')
 validpgpkeys=('19882D92DDA4C400C22C0D56CC2AF4472167BE03')
 
 prepare() {
   cd ${srcdir}/${pkgbase}-${pkgver}
+
+  # do not leak build-time LDFLAGS into the pkgconfig files:
+  # https://bugs.archlinux.org/task/68523
+  patch -p1 -i ${srcdir}/ncurses-6.3-pkgconfig.patch
 }
 
 build() {

ncurses/ncurses-6.3-pkgconfig.patch

@@ -0,0 +1,24 @@
+diff -ruN a/misc/gen-pkgconfig.in b/misc/gen-pkgconfig.in
+--- a/misc/gen-pkgconfig.in	2021-08-07 23:36:33.000000000 +0200
++++ b/misc/gen-pkgconfig.in	2021-11-03 11:12:51.127160950 +0100
+@@ -83,7 +83,7 @@
+ fi
+ 
+ lib_flags=
+-for opt in -L$libdir @EXTRA_PKG_LDFLAGS@ @LIBS@
++for opt in -L$libdir @LIBS@
+ do
+ 	case $opt in
+ 	-l*) # LIBS is handled specially below
+diff -ruN a/misc/ncurses-config.in b/misc/ncurses-config.in
+--- a/misc/ncurses-config.in	2021-08-07 23:36:14.000000000 +0200
++++ b/misc/ncurses-config.in	2021-11-03 11:26:12.393533954 +0100
+@@ -101,7 +101,7 @@
+ # There is no portable way to find the list of standard library directories.
+ # Require a POSIX shell anyway, to keep this simple.
+ lib_flags=
+-for opt in -L$libdir @EXTRA_PKG_LDFLAGS@ $LIBS
++for opt in -L$libdir $LIBS
+ do
+ 	case $opt in
+ 	-specs*) # ignore linker specs-files which were used to build library