diff --git a/FL/Fl_Graphics_Driver.H b/FL/Fl_Graphics_Driver.H
index 1bb3632f96a6b2c66afc3b1e9ebf325f631b091f..37210173a51e89abd9734d62e9f62d7b890e0cfb 100644
--- a/FL/Fl_Graphics_Driver.H
+++ b/FL/Fl_Graphics_Driver.H
@@ -57,7 +57,12 @@ typedef struct _PangoFontDescription PangoFontDescription;
 // See issue #1139: "FL_REGION_STACK_SIZE could be increased"
 // and issue #1140: "Fix static array allocation".
 
-#define FL_REGION_STACK_SIZE 64
+#if FL_ABI_VERSION >= 10401
+# define FL_REGION_STACK_SIZE 64
+#else
+# define FL_REGION_STACK_SIZE 10
+#endif
+
 #define FL_MATRIX_STACK_SIZE 32
 
 /**
diff --git a/FL/Fl_Help_View.H b/FL/Fl_Help_View.H
index 35fd44ee0ecfcf197dc0d5f4087d5731eb459629..6a59e58c81c2f8e7682d1fd7168f6098951a3da3 100644
--- a/FL/Fl_Help_View.H
+++ b/FL/Fl_Help_View.H
@@ -3,7 +3,7 @@
 //
 // Copyright 1997-2010 by Easy Software Products.
 // Image support by Matthias Melcher, Copyright 2000-2009.
-// Copyright 2011-2022 by Bill Spitzak and others.
+// Copyright 2011-2024 by Bill Spitzak and others.
 //
 // This library is free software. Distribution and use rights are outlined in
 // the file "COPYING" which should have been included with this file.  If this
@@ -225,7 +225,12 @@ class FL_EXPORT Fl_Help_View : public Fl_Group {        // Help viewer widget
                 atargets_;              ///< Allocated targets
   Fl_Help_Target *targets_;             ///< Targets
 
+#if FL_ABI_VERSION >= 10401
   char          directory_[2 * FL_PATH_MAX + 15]; ///< Directory for current file
+#else
+  char          directory_[FL_PATH_MAX]; ///< Directory for current file
+#endif
+
   char          filename_[FL_PATH_MAX]; ///< Current filename
   int           topline_,               ///< Top line in document
                 leftline_,              ///< Lefthand position