1 files changed, 24 insertions, 14 deletions
diff --git a/macosx/tkMacOSXFileTypes.c b/macosx/tkMacOSXFileTypes.c
index c89328d..66e4fbb 100644
--- a/macosx/tkMacOSXFileTypes.c
+++ b/macosx/tkMacOSXFileTypes.c
@@ -69,36 +69,46 @@ MODULE_SCOPE NSString *TkMacOSXOSTypeToUTI(OSType ostype) {
  * accept an NSString which could be an encoding of an OSType, or a file extension,
  * or a Uniform Type Idenfier.  This function can serve as a replacement.
  */
-
 MODULE_SCOPE NSImage *TkMacOSXIconForFileType(NSString *filetype) {
-#if MAC_OS_X_VERSION_MAX_ALLOWED >= 101300
     if (!initialized) {
 	initOSTypeTable();
     }
+#if MAC_OS_X_VERSION_MAX_ALLOWED < 110000
+// We don't have UTType but iconForFileType is not deprecated, so use it.
+    return [[NSWorkspace sharedWorkspace] iconForFileType:filetype];
+#else
+// We might have UTType but iconForFileType might be deprecated.
     if (@available(macOS 11.0, *)) {
+	/* Yes, we do have UTType */
 	UTType *uttype = [UTType typeWithIdentifier: filetype];
-	if (![uttype isDeclared]) {
+	if (uttype == nil || !uttype.isDeclared) {
 	    uttype = [UTType typeWithFilenameExtension: filetype];
 	}
-	if (![uttype isDeclared] && [filetype length] == 4) {
+	if (uttype == nil || (!uttype.isDeclared && filetype.length == 4)) {
 	    OSType ostype = CHARS_TO_OSTYPE(filetype.UTF8String);
 	    NSString *UTI = TkMacOSXOSTypeToUTI(ostype);
-	    uttype = [UTType typeWithIdentifier:UTI];
+	    if (UTI) {
+		uttype = [UTType typeWithIdentifier:UTI];
+	    }
 	}
-	if (![uttype isDeclared]) {
+	if (uttype == nil || !uttype.isDeclared) {
 	    return nil;
 	}
 	return [[NSWorkspace sharedWorkspace] iconForContentType:uttype];
     } else {
-/* Despite Apple's claims, @available does not prevent deprecation warnings. */ 
-# if MAC_OS_X_VERSION_MIN_REQUIRED < 110000
-	return [[NSWorkspace sharedWorkspace] iconForFileType:filetype];
-#else
-	return nil; /* Never executed. */
-#endif
-    }
-#else /* @available is not available. */
+	/* No, we don't have UTType. */
+ #if MAC_OS_X_VERSION_MIN_REQUIRED < 110000
+	/* but iconForFileType is not deprecated, so we can use it. */
     return [[NSWorkspace sharedWorkspace] iconForFileType:filetype];
+ #else
+    /*
+     * Cannot be reached: MIN_REQUIRED >= 110000 yet 11.0 is not available.
+     * But the compiler can't figure that out, so it will warn about an
+     * execution path with no return value unless we put a return here.
+     */
+    return nil;
+ #endif
+    }
 #endif
 }