diff --git a/harbour/ChangeLog b/harbour/ChangeLog
index 96c127d092..9aeb0cf4ed 100644
--- a/harbour/ChangeLog
+++ b/harbour/ChangeLog
@@ -17,6 +17,12 @@
    past entries belonging to author(s): Viktor Szakats.
 */
 
+2009-11-17 01:23 UTC+0100 Viktor Szakats (harbour.01 syenar.hu)
+  * contrib/gtwvg/Makefile
+  * external/libpng/Makefile
+    % Streamlined platform/compiler filtering logic plus more 
+      precise skip reason.
+
 2009-11-17 01:05 UTC+0100 Viktor Szakats (harbour.01 syenar.hu)
   * src/rdd/dbfntx/dbfntx1.c
   * src/rdd/dbfnsx/dbfnsx1.c
diff --git a/harbour/contrib/gtwvg/Makefile b/harbour/contrib/gtwvg/Makefile
index c0f0d99337..e93c59938a 100644
--- a/harbour/contrib/gtwvg/Makefile
+++ b/harbour/contrib/gtwvg/Makefile
@@ -52,20 +52,18 @@ PRG_HEADERS := \
    wvtwin.ch \
    wvgparts.ch \
 
-HB_SUPPORTED := no
 ifeq ($(HB_PLATFORM),win)
    ifneq ($(filter $(HB_COMPILER),mingw msvc msvc64 watcom pocc pocc64 icc bcc),)
-      HB_SUPPORTED := yes
+   
+      HB_INC_DEPEND := -I$(TOP)$(ROOT)contrib/hbwin
+   
+      include $(TOP)$(ROOT)config/header.mk
+      include $(TOP)$(ROOT)config/lib.mk
+   else
+      HB_SKIP_REASON := compiler not supported
+      include $(TOP)$(ROOT)config/none.mk
    endif
-endif
-
-ifeq ($(HB_SUPPORTED),yes)
-
-   HB_INC_DEPEND := -I$(TOP)$(ROOT)contrib/hbwin
-
-   include $(TOP)$(ROOT)config/header.mk
-   include $(TOP)$(ROOT)config/lib.mk
 else
-   HB_SKIP_REASON := platform or compiler not supported
+   HB_SKIP_REASON := platform not supported
    include $(TOP)$(ROOT)config/none.mk
 endif
diff --git a/harbour/external/libpng/Makefile b/harbour/external/libpng/Makefile
index 85cb59fcaa..3a746f437b 100644
--- a/harbour/external/libpng/Makefile
+++ b/harbour/external/libpng/Makefile
@@ -29,16 +29,7 @@ C_SOURCES := \
    pngwtran.c \
    pngwutil.c \
 
-# decide if it's supported at all
-HB_SUPPORTED := yes
-ifeq ($(HB_COMPILER),poccarm)
-   HB_SUPPORTED := no
-endif
-ifeq ($(HB_COMPILER),xcc)
-   HB_SUPPORTED := no
-endif
-
-ifeq ($(HB_SUPPORTED),yes)
+ifeq ($(filter $(HB_COMPILER),poccarm xcc),)
 
    _DET_DSP_NAME := libpng
    _DET_VAR_INC_ := HB_INC_PNG
@@ -70,6 +61,6 @@ ifeq ($(HB_SUPPORTED),yes)
       include $(TOP)$(ROOT)config/none.mk
    endif
 else
-   HB_SKIP_REASON := platform or compiler not supported
+   HB_SKIP_REASON := compiler not supported
    include $(TOP)$(ROOT)config/none.mk
 endif