diff -ur gnuplot-4.6.7/config/mingw/Makefile gnuplot-4.6.7-commit/config/mingw/Makefile
--- gnuplot-4.6.7/config/mingw/Makefile	2014-06-13 01:56:55.000000000 +0900
+++ gnuplot-4.6.7-commit/config/mingw/Makefile	2015-05-16 11:46:53.704000000 +0900
@@ -27,7 +27,7 @@
 
 # Use more modern HTML help instead of no longer supported Windows help system
 # Please update the HHWPATH below if necessary.
-HTML_HELP=1
+#HTML_HELP=1
 
 # GIF, PNG, JPEG device drivers
 # Requires gd library. There are two possibilities how to configure these
@@ -127,29 +127,29 @@
 # -mpentiumpro means optimize for Pentium II and Pro processors
 #CFLAGS +=
 
-ifdef HTML_HELP
+# ifdef HTML_HELP
 
 # To compile the .chm file you need the Microsoft HTML Help 1.4 SDK
 # It can be obtained here:
 # http://go.microsoft.com/fwlink/?LinkId=154968
 # We need to explicitly set the correct path here since we also need
 # adjust the include and library paths.
-HHWPATH = "$(PROGRAMFILES)/HTML Help Workshop/"
-HHC = $(HHWPATH)hhc
+# HHWPATH = "$(PROGRAMFILES)/HTML Help Workshop/"
+# HHC = $(HHWPATH)hhc
 
-else
+# else
 
 # To compile the .hlp file you need hcw either out of Microsoft SDK or MS Help
 # Workshop. The latter can be obtained from either of
 # ftp://ftp.microsoft.com/softlib/mslfiles/hcwsetup.exe
 # http://www.microsoft.com/downloads/details.aspx?displaylang=en&FamilyID=34D35502-4DE9-4676-952C-34CC7F64F098
 # Put the path to hcw here unless it is already in PATH:
-HCWPATH = "$(PROGRAMFILES)/Help\ Workshop/"
-HCW = $(HCWPATH)hcw
+# HCWPATH = "$(PROGRAMFILES)/Help\ Workshop/"
+# HCW = $(HCWPATH)hcw
 # Switches are for HCW 4.03:
-HCWFLAG =
+# HCWFLAG =
 
-endif
+# endif
 
 # Choose which resource compiler you want to use (GNU windres or MS rc):
 GNU_RC = 1
@@ -382,8 +382,9 @@
 endif
 
 ifdef ICONV
-	CFLAGS += -DHAVE_ICONV
-	TERMLIBS += -liconv
+	CFLAGS += -DHAVE_ICONV $(ICONV_CFLAGS)
+        LDFLAGS += $(ICONV_LDFLAGS)
+	TERMLIBS += -liconv 
 endif
 
 ifdef GNU_RC
@@ -401,7 +402,7 @@
   RES2COFF = res2coff -i wgnuplot.res -o wgplt_res.$(O)
 endif
 
-default: $(TARGET) $(MENUFILE) support
+default: $(TARGET) $(MENUFILE) # support
 
 console:
 	$(MAKE) TARGET=gnuplot.exe gnuplot.exe
@@ -443,7 +444,7 @@
   LDFLAGS2 += -L$(HHWPATH)lib
 endif
 
-$(TARGET): $(OBJS) $(WINOBJS) wgplt_res.$(O) texticon.ico grpicon.ico
+$(TARGET): $(OBJS) $(WINOBJS) wgplt_res.$(O) TEXTICON.ico GRPICON.ico
 	$(LDX) $(LDFLAGS) $(LDFLAGS2) -o $@ $(OBJS) $(WINOBJS) wgplt_res.$(O) $(LDLIBS)\
 	$(TERMLIBS) $(WX_LIBS) $(PANGOCAIRO_LIBS)
 
@@ -458,7 +459,7 @@
 
 # explicit rules
 
-wgplt_res.$(O): $(W)/wgnuplot.rc $(W)/wgnuplib.rc $(W)/wresourc.h texticon.ico grpicon.ico
+wgplt_res.$(O): $(W)/wgnuplot.rc $(W)/wgnuplib.rc $(W)/wresourc.h TEXTICON.ico GRPICON.ico
 	$(RC) $(RCFLAGS) $< $(RCOUT)
 	$(RES2COFF)
 
@@ -494,13 +495,13 @@
 	$(CC) -c $(CFLAGS) $(CXXFLAGS) $(PANGOCAIRO_CFLAGS) -MMD -MT '$*.$$(O)' -MF $*.d -o $@ $<
 
 # extract icons from wgnuplot.rc
-texticon.ico: grpicon.ico
+TEXTICON.ico: GRPICON.ico
 
-grpicon.ico: geticon.exe $(W)/wgnuplot.rc
+GRPICON.ico: geticon $(W)/wgnuplot.rc
 	./geticon $(W)/wgnuplot.rc
 
-geticon.exe: $(W)/geticon.c
-	$(LD) $(LDFLAGS) -o $@ $<
+geticon: $(W)/geticon.c
+	gcc -o $@ $<
 
 ifdef HTML_HELP
 # convert gnuplot.doc to windows/wgnuplot.html
@@ -703,7 +704,7 @@
 	$(RM) config.h wgnuplot.map wgnuplot.res $(W)/gnuplot.rtf
 	$(RM) *.$(O) *.po *.o *.co *.d
 	$(RM) doc2*.exe $(W)/wgnuplib.res wgnuplib.map wgnuplot.lib
-	$(RM) $(M)bf_test.exe *.ico geticon.exe allterm.h allterm.c
+	$(RM) $(M)bf_test.exe *.ico geticon allterm.h allterm.c
 	$(RM) *.aux *.log *.dvi *.toc
 	$(RM) gnuplot.tex gnuplot-figures.tex pdffigures.tex figure_*.pdf
 	$(RM) titlepag.tex toc_entr.sty VERSION
@@ -802,7 +803,7 @@
 
 installer:
 	$(MAKE) DESTDIR=./dist install
-	cp -p grpicon.ico ./dist/bin/
+	cp -p GRPICON.ico ./dist/bin/
 	cp -p $(TOP)/win/*.iss ./dist
 	(cd ./dist; $(ISCC) gnuplot.iss)
 ifdef RELEASE

diff -ur gnuplot-4.6.7/src/syscfg.h gnuplot-4.6.7-commit/src/syscfg.h
--- gnuplot-4.6.7/src/syscfg.h	2014-08-01 01:56:25.000000000 +0900
+++ gnuplot-4.6.7-commit/src/syscfg.h	2015-05-16 15:27:58.612000000 +0900
@@ -317,11 +317,19 @@
 #endif
 
 #ifndef GP_EXCEPTION_NAME
-# define GP_EXCEPTION_NAME exception
+# if __MINGW32__
+#  define GP_EXCEPTION_NAME _exception
+# else
+#  define GP_EXCEPTION_NAME exception
+# endif
 #endif
 
 #ifndef GP_MATHERR
-# define GP_MATHERR matherr
+# if __MINGW32__
+#  define GP_MATHERR _matherr
+# else
+#  define GP_MATHERR matherr
+# endif
 #endif
 
 #ifdef HAVE_STRUCT_EXCEPTION_IN_MATH_H

diff -ur gnuplot-4.6.7/src/win/wgnuplot.rc gnuplot-4.6.7-commit/src/win/wgnuplot.rc
--- gnuplot-4.6.7/src/win/wgnuplot.rc	2014-07-08 03:18:41.000000000 +0900
+++ gnuplot-4.6.7-commit/src/win/wgnuplot.rc	2015-05-16 11:24:48.912000000 +0900
@@ -19,8 +19,8 @@
    * rc -30 -k -dMSRC win\wgnuplot.rc wgnuplot.exe
    */
 
-GRPICON ICON "grpicon.ico"
-TEXTICON ICON  "texticon.ico"
+GRPICON ICON "GRPICON.ico"
+TEXTICON ICON  "TEXTICON.ico"
 
 #else
 /* using Borland BRC.EXE */

diff -ur internal.orig.c internal.mod.c
--- a/src/internal.c	2014-07-08 03:18:40.000000000 +0900
+++ b/src/internal.c	2015-05-16 19:29:17.660000000 +0900
@@ -58,6 +58,7 @@
 
 static enum DATA_TYPES sprintf_specifier __PROTO((const char *format));
 
+#ifndef __MINGW32__
 #ifndef _WIN64
 int
 GP_MATHERR( STRUCT_EXCEPTION_P_X )
@@ -65,6 +66,7 @@
     return (undefined = TRUE);	/* don't print error message */
 }
 #endif
+#endif
 
 #define BAD_DEFAULT default: int_error(NO_CARET, "internal error : type neither INT or CMPLX"); return;