Check for PKG_CONFIG_LIBDIR when cross compiling.

When cross-compiling, check for PKG_CONFIG_LIBDIR instead of
PKG_CONFIG_PATH. pkg-config searches for pc files in PKG_CONFIG_PATH
*and* the compiled in defaults (/usr/lib/pkgconfig). This means that
pc files from the host get found when cross-compiling.

Setting PKG_CONFIG_LIBDIR makes pkg-config search only in the path
set in PKG_CONFIG_LIBDIR.

Documented in the url below:
http://www.freedesktop.org/wiki/Software/pkg-config/CrossCompileProposal

Change-Id: I22dbf29c5691572b7cb8a5fce712ae7ba811670e
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@nokia.com>

diff --git a/configure b/configure
index 66c5f1a..e2df602 100755 (executable)
--- a/configure
+++ b/configure
@@ -2625,11 +2625,11 @@ if [ "$QT_CROSS_COMPILE" = "yes" ]; then
         echo >&2 "Please make sure you have a correctly set-up pkg-config"
         echo >&2 "environment!"
         echo >&2 ""
-        if [ -z "$PKG_CONFIG_PATH" ]; then
+        if [ -z "$PKG_CONFIG_LIBDIR" ]; then
             echo >&2 ""
-            echo >&2 "Warning: PKG_CONFIG_PATH has not been set.  This could mean"
-            echo >&2 "the host compiler's .pc files will be used. This is probably"
-            echo >&2 "not what you want."
+            echo >&2 "Warning: PKG_CONFIG_LIBDIR has not been set.  This could mean"
+            echo >&2 "the host's .pc files will be used (even if you set PKG_CONFIG_PATH)."
+            echo >&2 "This is probably not what you want."
             echo >&2 ""
         elif [ -z "$PKG_CONFIG_SYSROOT" ] && [ -z "$PKG_CONFIG_SYSROOT_DIR" ]; then
             echo >&2 ""