diff --git a/Makefile b/Makefile
index 31481b5..a7d6e36 100644
--- a/Makefile
+++ b/Makefile
@@ -213,10 +213,10 @@ ALIGN32= -DMUST_ALIGN32
 # MAIN= -DMAIN=void	main() is of type void
 # MAIN= -DMAIN=int	main() is of type int
 #
-# When in doubt, try MAIN= -DMAIN=void.  If you get a warning try the other.
+# When in doubt, try MAIN= -DMAIN=int.  If you get a warning try the other.
 #
-MAIN= -DMAIN=void
-#MAIN= -DMAIN=int
+#MAIN= -DMAIN=void
+MAIN= -DMAIN=int
 
 # where to install binary files
 #
@@ -332,7 +332,7 @@ CALCPAGER= more
 
 # Debug/Optimize options for ${CC}
 #
-DEBUG= -O
+#DEBUG= -O
 #DEBUG= -O -g
 #DEBUG= -O -g3
 #DEBUG= -O1
@@ -340,7 +340,7 @@ DEBUG= -O
 #DEBUG= -O1 -g3
 #DEBUG= -O2
 #DEBUG= -O2 -g
-#DEBUG= -O2 -g3
+DEBUG= -O2 -g3
 #DEBUG= -O2 -ipa
 #DEBUG= -O2 -g3 -ipa
 #DEBUG= -O3
@@ -388,8 +388,8 @@ LD_NO_SHARED=
 # a *.a library.  Set RANLIB to the utility that performs this action.
 # Set RANLIB to : if your system does not need such a utility.
 #
-#RANLIB=ranlib
-RANLIB=:
+RANLIB=ranlib
+#RANLIB=:
 
 # Some systems are able to form lint libs.  How it is formed depends
 # on your system.  If you do not care about lint, use : as the
@@ -507,21 +507,21 @@ ALLOW_CUSTOM= -DCUSTOM
 #
 # common cc set
 #
-CCWARN=
-CCOPT= ${DEBUG} ${NO_SHARED}
-CCMISC=
+#CCWARN=
+#CCOPT= ${DEBUG} ${NO_SHARED}
+#CCMISC=
 #
-CFLAGS= ${CCWARN} ${CCOPT} ${CCMISC}
-ICFLAGS= ${CCWARN} ${CCMISC}
+#CFLAGS= ${CCWARN} ${CCOPT} ${CCMISC}
+#ICFLAGS= ${CCWARN} ${CCMISC}
 #
-CCMAIN= ${ICFLAGS} ${MAIN}
-CCSHS= ${CFLAGS}
+#CCMAIN= ${ICFLAGS} ${MAIN}
+#CCSHS= ${CFLAGS}
 #
-LCFLAGS=
-LDFLAGS= ${NO_SHARED} ${LD_NO_SHARED}
-ILDFLAGS=
+#LCFLAGS=
+#LDFLAGS= ${NO_SHARED} ${LD_NO_SHARED}
+#ILDFLAGS=
 #
-CC= ${PURIFY} cc
+#CC= ${PURIFY} cc
 #
 ###
 #
@@ -680,61 +680,37 @@ CC= ${PURIFY} cc
 #
 ###
 #
-# gcc set
+# Red Hat Linux 6.0
 #
 # for better performance, set the following above:
-#     DEBUG= -O
+#     DEBUG= -O2
 #
-#CCWARN= -Wall
-#CCOPT= ${DEBUG} ${NO_SHARED}
-#CCMISC= -ansi
+CCWARN= -Wall -Wno-implicit -Wno-comment
+CCOPT= ${DEBUG} ${NO_SHARED}
+CCMISC=
 #
-#CFLAGS= ${CCWARN} ${CCOPT} ${CCMISC}
-#ICFLAGS= ${CCWARN} ${CCMISC}
+CFLAGS= ${CCWARN} ${CCOPT} ${CCMISC}
+ICFLAGS= ${CCWARN} ${CCMISC}
 #
-#CCMAIN= ${ICFLAGS} ${MAIN}
-#CCSHS= ${CFLAGS}
+CCMAIN= ${ICFLAGS} ${MAIN}
+CCSHS= ${CFLAGS}
 #
-#LCFLAGS=
-#LDFLAGS= ${NO_SHARED} ${LD_NO_SHARED}
-#ILDFLAGS=
+LCFLAGS=
+LDFLAGS= ${NO_SHARED} ${LD_NO_SHARED}
+ILDFLAGS=
 #
-#CC= ${PURIFY} gcc
+CC= ${PURIFY} gcc
 #
 ###
 #
-# gcc1 set	(some call it gcc1, some call it gcc)
-#
-# for better performance, set the following above:
-#     DEBUG= -O
-#
-#CCWARN= -Wall
-#CCOPT= ${DEBUG} ${NO_SHARED}
-#CCMISC= -ansi
-#
-#CFLAGS= ${CCWARN} ${CCOPT} ${CCMISC}
-#ICFLAGS= ${CCWARN} ${CCMISC}
-#
-#CCMAIN= ${ICFLAGS} ${MAIN}
-#CCSHS= ${CFLAGS}
-#
-#LCFLAGS=
-#LDFLAGS= ${NO_SHARED} ${LD_NO_SHARED}
-#ILDFLAGS=
-#
-#CC= ${PURIFY} gcc1
-#CC= ${PURIFY} gcc
-#
-###
-#
-# gcc2 set	(some call it gcc2, some call it gcc)
+# gcc set	(some call it gcc2, some call it gcc)
 #
 # for better performance, set the following above:
 #     DEBUG= -O2
 #
 #CCWARN= -Wall -Wno-implicit -Wno-comment
 #CCOPT= ${DEBUG} ${NO_SHARED}
-#CCMISC= -ansi
+#CCMISC=
 #
 #CFLAGS= ${CCWARN} ${CCOPT} ${CCMISC}
 #ICFLAGS= ${CCWARN} ${CCMISC}
@@ -746,8 +722,8 @@ CC= ${PURIFY} cc
 #LDFLAGS= ${NO_SHARED} ${LD_NO_SHARED}
 #ILDFLAGS=
 #
-#CC= ${PURIFY} gcc2
 #CC= ${PURIFY} gcc
+#CC= ${PURIFY} gcc2
 
 ##############################################################################
 #-=-=-=-=-=-=-=-=- Be careful if you change something below -=-=-=-=-=-=-=-=-#
diff --git a/func.c b/func.c
index 0958b8b..1b0b10f 100644
--- a/func.c
+++ b/func.c
@@ -77,9 +77,9 @@ static VALUE f_fsize(VALUE *vp);
 /*
  * external declarations
  */
-extern int errno;				/* last system error */
-extern char *sys_errlist[];			/* system error messages */
-extern int sys_nerr;				/* number of system errors */
+extern int errno;                             /* last system error */
+extern const char *const sys_errlist[];       /* system error messages */
+extern int sys_nerr;                          /* number of system errors */
 extern char cmdbuf[];				/* command line expression */
 extern CONST char *error_table[E__COUNT+2];	/* calc coded error messages */
 extern void matrandperm(MATRIX *M);
diff --git a/longbits.c b/longbits.c
index e655321..9b8d6ac 100644
--- a/longbits.c
+++ b/longbits.c
@@ -97,6 +97,12 @@
 
 #include "longlong.h"
 
+#if defined(__linux)
+# if !defined(isascii)
+   extern int isascii(int c);
+# endif /* !isascii */
+#endif /* __linux */
+
 char *program;		/* our name */
 
 MAIN
diff --git a/version.c b/version.c
index 1e73276..feb9782 100644
--- a/version.c
+++ b/version.c
@@ -10,9 +10,9 @@
 #include "calc.h"
 
 #define MAJOR_VER	2	/* major version */
-#define MINOR_VER	10	/* minor version */
-#define MAJOR_PATCH	3	/* patch level or 0 if no patch */
-#define MINOR_PATCH	"t5.46"	/* test number or empty string if no patch */
+#define MINOR_VER	11	/* minor version */
+#define MAJOR_PATCH	0	/* patch level or 0 if no patch */
+#define MINOR_PATCH	"0"	/* test number or empty string if no patch */
 
 /*
  * calc version constants