From b9f06bf05b67239cea80998a747f73a2ed3e7be6 Mon Sep 17 00:00:00 2001
From: Hennadii Stepanov <32963518+hebasto@users.noreply.github.com>
Date: Sat, 23 Jul 2022 23:31:01 +0100
Subject: [PATCH] build: Do not export `PKG_CONFIG_{PATH|LIBDIR}` variables

---
 configure.ac           | 10 ++++++++++
 depends/config.site.in |  7 ++-----
 2 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/configure.ac b/configure.ac
index 90e7f18515e00..924bfd35abec8 100644
--- a/configure.ac
+++ b/configure.ac
@@ -19,6 +19,16 @@ if test "$PKG_CONFIG" = ""; then
   AC_MSG_ERROR([pkg-config not found])
 fi
 
+# When compiling with depends, the `PKG_CONFIG_PATH` and `PKG_CONFIG_LIBDIR` variables,
+# being set in a `config.site` file, are not exported to let the `--config-cache` option
+# work properly.
+if test -n "$PKG_CONFIG_PATH"; then
+  PKG_CONFIG="env PKG_CONFIG_PATH=$PKG_CONFIG_PATH $PKG_CONFIG"
+fi
+if test -n "$PKG_CONFIG_LIBDIR"; then
+  PKG_CONFIG="env PKG_CONFIG_LIBDIR=$PKG_CONFIG_LIBDIR $PKG_CONFIG"
+fi
+
 BITCOIN_DAEMON_NAME=bitcoind
 BITCOIN_GUI_NAME=bitcoin-qt
 BITCOIN_CLI_NAME=bitcoin-cli
diff --git a/depends/config.site.in b/depends/config.site.in
index f7e770343c4f9..8f6849214d164 100644
--- a/depends/config.site.in
+++ b/depends/config.site.in
@@ -84,12 +84,9 @@ fi
 
 PKG_CONFIG="$(which pkg-config) --static"
 
-# These two need to remain exported because pkg-config does not see them
-# otherwise. That means they must be unexported at the end of configure.ac to
-# avoid ruining the cache. Sigh.
-export PKG_CONFIG_PATH="${depends_prefix}/share/pkgconfig:${depends_prefix}/lib/pkgconfig"
+PKG_CONFIG_PATH="${depends_prefix}/share/pkgconfig:${depends_prefix}/lib/pkgconfig"
 if test -z "@allow_host_packages@"; then
-  export PKG_CONFIG_LIBDIR="${depends_prefix}/lib/pkgconfig"
+  PKG_CONFIG_LIBDIR="${depends_prefix}/lib/pkgconfig"
 fi
 
 CPPFLAGS="-I${depends_prefix}/include/ ${CPPFLAGS}"