--- /usr/local/bin/portlint	2017-08-17 03:23:21.000000000 +0200
+++ portlint	2017-11-17 13:23:00.903113000 +0100
@@ -153,7 +153,7 @@
 	WRKDIR WRKSRC NO_WRKSUBDIR SCRIPTDIR FILESDIR
 	PKGDIR COMMENT DESCR PLIST PKGCATEGORY PKGINSTALL PKGDEINSTALL
 	PKGREQ PKGMESSAGE DISTINFO_FILE .CURDIR USE_LDCONFIG USE_AUTOTOOLS
-	USE_GNOME USE_PERL5 INDEXFILE PKGORIGIN CONFLICTS PKG_VERSION
+	USE_GNOME USE_PERL5 USE_QT5 INDEXFILE PKGORIGIN CONFLICTS PKG_VERSION
 	PLIST_FILES PLIST_DIRS PORTDOCS PORTEXAMPLES
 	OPTIONS_DEFINE OPTIONS_RADIO OPTIONS_SINGLE OPTIONS_MULTI
 	OPTIONS_GROUP OPTIONS_SUB INSTALLS_OMF USE_RC_SUBR USES DIST_SUBDIR
@@ -776,7 +776,8 @@
 		}
 
 		if ($_ =~ m|^share/icons/.*/| &&
-			$makevar{INSTALLS_ICONS} eq '') {
+			$makevar{INSTALLS_ICONS} eq '' &&
+			needs_installs_icons()) {
 			&perror("WARN", $file, $., "installing icons, ".
 				"please define INSTALLS_ICONS as appropriate");
 		}
@@ -1476,7 +1477,8 @@
 					"If possible, install this file with a different name.");
 			}
 			if ($plist_file =~ m|^share/icons/.*/| &&
-				$makevar{INSTALLS_ICONS} eq '') {
+				$makevar{INSTALLS_ICONS} eq '' &&
+				needs_installs_icons()) {
 				&perror("WARN", "", -1, "PLIST_FILES: installing icons, ".
 					"please define INSTALLS_ICONS as appropriate");
 			}
@@ -1825,6 +1827,14 @@
 	}
 
 	#
+	# whole file: using INSTALLS_ICONS when it is not wanted
+	#
+	if (!($makevar{INSTALLS_ICONS} eq '') &&
+		!needs_installs_icons()) {
+		&perror("WARN", $file, -1, "INSTALLS_ICONS is set, but should not be.");
+	}
+
+	#
 	# whole file: EXPIRATION_DATE
 	#
 	print "OK: checking for valid EXPIRATION_DATE.\n" if ($verbose);
@@ -3570,6 +3580,12 @@
 }
 sub TRUE {1;}
 
+# GNOME wants INSTALL_ICONS, but Qt-based applications, including KDE, don't.
+# Be pessimistic: everything needs it unless we know it doesn't.
+sub needs_installs_icons {
+	return $makevar{USE_QT5} eq ''
+}
+
 # Local variables:
 # tab-width: 4
 # End: