diff --git a/CHANGES b/CHANGES
index b13be92..73deb77 100644
--- a/CHANGES
+++ b/CHANGES
@@ -260,6 +260,78 @@ The following are the changes from calc version 2.12.0 to date:
     Updated the "help variable" text to reflect the current calc
     use of ` (backquote), * (star), and & (ampersand).
 
+    Removal of some restrictions on the use of the same identifier
+    for more than one of parameter, local, static or global variable.
+
+	For example, at command level, one could use:
+
+	    for (local x = 0; x < 10; x++) print sqrt(x);
+
+	At the beginning of a statement, "(global A)" is a way of
+	indicating a reference to the variable A, whereas "global A"
+	would be taken as a declaration. Parentheses are not required in
+	"++global A" or "global A++" when "global" is used in this way.
+
+	The patch extends this "specifier" (or "qualifier") feature
+	to static variables, but such that "static A" refers only
+	to a static variable at the current file and function scope
+	levels. (If there is already a static variable A at the current
+	file and function levels, a declaration statement "static A"
+	would end the scope of that variable and define a new static
+	variable with identifier A. A "global A" declaration is more
+	drastic in that it ends the scope of any static variable A at
+	the same or higher scope levels.)
+
+	Unlike a static declaration in which an "initialization" occurs at
+	most once, in the specifier case, "static A = expr" is simply an
+	assignment which may be repeated any number of times.  An example
+	of its use is:
+
+	    define np() = static a = nextprime(a);
+
+	For n not too large, the n-th call to this function will
+	return the n-th prime. The variable a here will be private to
+	the function.
+
+	Because one can use "global", "local" or "static" to specify a
+	type of variable, there seems little point in restricting the
+	ways identifiers that can be used in more than one of these
+	or as parameters. Obviously, introducing A as a local variable
+	when it is being used as a parameter can lead to confusion and a
+	warning is appropriate, but if it is to be used only occasionally,
+	it might be convenient to be able to refer to it as "local A"
+	rather than introducing another identifier. While it may be
+	silly to use the same identifier for both a parameter and local
+	variable, it should not be illegal.
+
+    The provision of warnings for possibly questionable programming in
+    function definitions.
+
+    Added config("redecl_warn", boolean) to control if calc issues
+    warnings about variables being declared.  The config("redecl_warn")
+    value is TRUE by default.
+
+    Added config("dupvar_warn", boolean) to control if calc issues
+    warnings about when variable names collide.  Examples of variable name
+    collisions include when:
+
+    	* both local and static variables have the same name
+    	* both local and global variables have the same name
+    	* both function parameter and local variables have the same name
+    	* both function parameter and global variables have the same name
+
+    The config("dupvar_warn") value is TRUE by default.
+
+    Fix of a bug which causes some static variables not to be correctly
+    unscoped when their identifiers are used in a global declaration.
+
+    Change of "undefine" from a command-level keyword to statement level and
+    introduction of an "undefine static A" statement to end the scope of a
+    static variable A at the current file/function levels.
+
+    Change/restored the syntax rules for "for" and "while" loops to
+    recognize an unescaped newline in top-level command-level statements.
+
 
 The following are the changes from calc version 2.11.10.1 to 2.11.11:
 
@@ -6077,8 +6149,8 @@ Following is a list of visible changes to calc from version 1.24.7 to 1.26.1:
 ## received a copy with calc; if not, write to Free Software Foundation, Inc.
 ## 59 Temple Place, Suite 330, Boston, MA  02111-1307, USA.
 ##
-## @(#) $Revision: 29.80 $
-## @(#) $Id: CHANGES,v 29.80 2006/06/11 07:52:58 chongo Exp $
+## @(#) $Revision: 29.82 $
+## @(#) $Id: CHANGES,v 29.82 2006/06/20 10:26:41 chongo Exp $
 ## @(#) $Source: /usr/local/src/cmd/calc/RCS/CHANGES,v $
 ##
 ## Under source code control:	1993/06/02 18:12:57
diff --git a/addop.c b/addop.c
index 1083391..a596b81 100644
--- a/addop.c
+++ b/addop.c
@@ -19,8 +19,8 @@
  * received a copy with calc; if not, write to Free Software Foundation, Inc.
  * 59 Temple Place, Suite 330, Boston, MA  02111-1307, USA.
  *
- * @(#) $Revision: 29.12 $
- * @(#) $Id: addop.c,v 29.12 2006/06/03 22:47:28 chongo Exp $
+ * @(#) $Revision: 29.13 $
+ * @(#) $Id: addop.c,v 29.13 2006/06/20 10:28:06 chongo Exp $
  * @(#) $Source: /usr/local/src/cmd/calc/RCS/addop.c,v $
  *
  * Under source code control:	1990/02/15 01:48:10
@@ -280,13 +280,13 @@ rmuserfunc(char *name)
 
 	index = findstr(&funcnames, name);
 	if (index < 0) {
-		errorcount--;
-		scanerror(T_NULL,
-		"Attempt to undefine an undefined function\n\t\"%s\"", name);
+		warning("No function named \"%s\" to be undefined", name);
 		return;
 	}
-	if (functions[index] == NULL)
+	if (functions[index] == NULL) {
+		warning("No defined function \"%s\" to be undefined", name);
 		return;
+	}
 	freenumbers(functions[index]);
 	free(functions[index]);
 	if ((inputisterminal() && conf->resource_debug & RSCDBG_STDIN_FUNC) ||
@@ -527,8 +527,7 @@ addop(long op)
 			fp->f_opcodecount -= diff;
 			oldop = OP_NOP;
 			oldoldop = OP_NOP;
-			errorcount--;
-			scanerror(T_NULL, "Constant before comma operator");
+			warning("Constant before comma operator");
 			return;
 		}
 		break;
diff --git a/cal/ellip.cal b/cal/ellip.cal
index 3484bba..55b9407 100644
--- a/cal/ellip.cal
+++ b/cal/ellip.cal
@@ -17,8 +17,8 @@
  * received a copy with calc; if not, write to Free Software Foundation, Inc.
  * 59 Temple Place, Suite 330, Boston, MA  02111-1307, USA.
  *
- * @(#) $Revision: 29.3 $
- * @(#) $Id: ellip.cal,v 29.3 2006/03/07 22:16:25 chongo Exp $
+ * @(#) $Revision: 29.4 $
+ * @(#) $Id: ellip.cal,v 29.4 2006/06/20 09:29:16 chongo Exp $
  * @(#) $Source: /usr/local/src/cmd/calc/cal/RCS/ellip.cal,v $
  *
  * Under source code control:	1990/02/15 01:50:33
@@ -28,16 +28,17 @@
  */
 
 /*
- * Attempt to factor numbers using elliptic functions.
- *	y^2 = x^3 + a*x + b   (mod N).
+ * Attempt to factor numbers using elliptic functions:
  *
- * Many points (x,y) (mod N) are found that solve the above equation,
+ *	y^2 = x^3 + a*x + b   (mod ellip_N).
+ *
+ * Many points (x,y) (mod ellip_N) are found that solve the above equation,
  * starting from a trivial solution and 'multiplying' that point together
  * to generate high powers of the point, looking for such a point whose
- * order contains a common factor with N.  The order of the group of points
- * varies almost randomly within a certain interval for each choice of a
- * and b, and thus each choice provides an independent opportunity to
- * factor N.  To generate a trivial solution, a is chosen and then b is
+ * order contains a common factor with ellip_N.  The order of the group of
+ * points varies almost randomly within a certain interval for each choice of
+ * a and b, and thus each choice provides an independent opportunity to
+ * factor ellip_N.  To generate a trivial solution, a is chosen and then b is
  * selected so that (1,1) is a solution.  The multiplication is done using
  * the basic fact that the equation is a cubic, and so if a line hits the
  * curve in two rational points, then the third intersection point must
@@ -45,9 +46,9 @@
  * the number of rational solutions can be made very large.  When modular
  * arithmetic is used, solving for the third point requires the taking of a
  * modular inverse (instead of division), and if this fails, then the GCD
- * of the failing value and N provides a factor of N.  This description is
- * only an approximation, read "A Course in Number Theory and Cryptography"
- * by Neal Koblitz for a good explanation.
+ * of the failing value and ellip_N provides a factor of ellip_N.
+ * This description is only an approximation, read "A Course in Number
+ * Theory and Cryptography" by Neal Koblitz for a good explanation.
  *
  * efactor(iN, ia, B, force)
  *	iN is the number to be factored.
@@ -81,15 +82,15 @@
  *
  * If a factor is found, it is returned and is also saved in the global
  * variable f.	The number being factored is also saved in the global
- * variable N.
+ * variable ellip_N.
  */
 
 
 obj point {x, y};
-global	N;		/* number to factor */
-global	a;		/* first coefficient */
-global	b;		/* second coefficient */
-global	f;		/* found factor */
+global	ellip_N;		/* number to factor */
+global	ellip_a;		/* first coefficient */
+global	ellip_b;		/* second coefficient */
+global	ellip_f;		/* found factor */
 
 
 define efactor(iN, ia, B, force)
@@ -103,28 +104,28 @@ define efactor(iN, ia, B, force)
 	if (isnull(ia))
 		ia = 1;
 	obj point x;
-	a = ia;
-	b = -ia;
-	N = iN;
-	C = isqrt(N);
+	ellip_a = ia;
+	ellip_b = -ia;
+	ellip_N = iN;
+	C = isqrt(ellip_N);
 	C = 2 * C + 2 * isqrt(C) + 1;
-	f = 0;
-	while (f == 0) {
-		print "A =", a;
+	ellip_f = 0;
+	while (ellip_f == 0) {
+		print "A =", ellip_a;
 		x.x = 1;
 		x.y = 1;
 		print 2, x;
 		x = x ^ (2 ^ (highbit(C) + 1));
-		for (p = 3; ((p < B) && (f == 0)); p += 2) {
+		for (p = 3; ((p < B) && (ellip_f == 0)); p += 2) {
 			if (!ptest(p, 1))
 				continue;
 			print p, x;
 			x = x ^ (p ^ ((highbit(C) // highbit(p)) + 1));
 		}
-		a++;
-		b--;
+		ellip_a++;
+		ellip_b--;
 	}
-	return f;
+	return ellip_f;
 }
 
 
@@ -143,16 +144,16 @@ define point_mul(p1, p2)
 	if (p1 == p2)
 		return point_square(`p1);
 	obj point r;
-	m = (minv(p2.x - p1.x, N) * (p2.y - p1.y)) % N;
+	m = (minv(p2.x - p1.x, ellip_N) * (p2.y - p1.y)) % ellip_N;
 	if (m == 0) {
-		if (f == 0)
-			f = gcd(p2.x - p1.x, N);
+		if (ellip_f == 0)
+			ellip_f = gcd(p2.x - p1.x, ellip_N);
 		r.x = 1;
 		r.y = 1;
 		return r;
 	}
-	r.x = (m^2 - p1.x - p2.x) % N;
-	r.y = ((m * (p1.x - r.x)) - p1.y) % N;
+	r.x = (m^2 - p1.x - p2.x) % ellip_N;
+	r.y = ((m * (p1.x - r.x)) - p1.y) % ellip_N;
 	return r;
 }
 
@@ -162,16 +163,16 @@ define point_square(p)
 	local	r, m;
 
 	obj point r;
-	m = ((3 * p.x^2 + a) * minv(p.y << 1, N)) % N;
+	m = ((3 * p.x^2 + ellip_a) * minv(p.y << 1, ellip_N)) % ellip_N;
 	if (m == 0) {
-		if (f == 0)
-			f = gcd(p.y << 1, N);
+		if (ellip_f == 0)
+			ellip_f = gcd(p.y << 1, ellip_N);
 		r.x = 1;
 		r.y = 1;
 		return r;
 	}
-	r.x = (m^2 - p.x - p.x) % N;
-	r.y = ((m * (p.x - r.x)) - p.y) % N;
+	r.x = (m^2 - p.x - p.x) % ellip_N;
+	r.y = ((m * (p.x - r.x)) - p.y) % ellip_N;
 	return r;
 }
 
@@ -184,7 +185,7 @@ define point_pow(p, pow)
 	if (isodd(pow))
 		r = p;
 	t = p;
-	for (bit = 2; ((bit <= pow) && (f == 0)); bit <<= 1) {
+	for (bit = 2; ((bit <= pow) && (ellip_f == 0)); bit <<= 1) {
 		t = point_square(`t);
 		if (bit & pow)
 			r = point_mul(`t, `r);
diff --git a/cal/prompt.cal b/cal/prompt.cal
index f6e2e64..3535dd0 100644
--- a/cal/prompt.cal
+++ b/cal/prompt.cal
@@ -17,8 +17,8 @@
  * received a copy with calc; if not, write to Free Software Foundation, Inc.
  * 59 Temple Place, Suite 330, Boston, MA  02111-1307, USA.
  *
- * @(#) $Revision: 29.2 $
- * @(#) $Id: prompt.cal,v 29.2 2000/06/07 14:02:25 chongo Exp $
+ * @(#) $Revision: 29.3 $
+ * @(#) $Id: prompt.cal,v 29.3 2006/06/20 09:29:16 chongo Exp $
  * @(#) $Source: /usr/local/src/cmd/calc/cal/RCS/prompt.cal,v $
  *
  * Under source code control:	1995/12/18 04:43:25
@@ -101,7 +101,7 @@ define adder() {
 	}
 }
 
-global x;
+global prompt_x;
 
 define showvalues(str) {
 	local s;
@@ -109,8 +109,8 @@ define showvalues(str) {
 		s = prompt("? ");
 		if (s == "end")
 			break;
-		x = eval(s);
-		if (!isnum(x)) {
+		prompt_x = eval(s);
+		if (!isnum(prompt_x)) {
 			print "Please enter a number";
 			continue;
 		}
diff --git a/cal/regress.cal b/cal/regress.cal
index 3f238d9..2824ab1 100644
--- a/cal/regress.cal
+++ b/cal/regress.cal
@@ -17,8 +17,8 @@
  * received a copy with calc; if not, write to Free Software Foundation, Inc.
  * 59 Temple Place, Suite 330, Boston, MA  02111-1307, USA.
  *
- * @(#) $Revision: 29.29 $
- * @(#) $Id: regress.cal,v 29.29 2006/06/11 07:07:23 chongo Exp $
+ * @(#) $Revision: 29.31 $
+ * @(#) $Id: regress.cal,v 29.31 2006/06/20 10:25:00 chongo Exp $
  * @(#) $Source: /usr/local/src/cmd/calc/cal/RCS/regress.cal,v $
  *
  * Under source code control:	1990/02/15 01:50:36
@@ -201,7 +201,6 @@ define test_variables()
 	local	x1, x2, x3;
 	global	g1, g2;
 	local	t;
-	global	globalvar;
 	local x;
 
 	print '350: Beginning test_variables';
@@ -3972,7 +3971,7 @@ print '088: parsed test_fileop()';
 /*
  * global and static assignment tests
  */
-global a = 10, b, c d = 20, e, f;
+global a = 10, b, c d = 20, e;
 print			'089: global a = 10, b, c d = 20, e, f';
 vrfy(a == 10,		'090: a == 10');
 vrfy(b == 0,		'091: b == 0');
@@ -4672,13 +4671,11 @@ print '137: parsed test_random()';
 /*
  * test_newsyn - test new command completion syntax and scope rules
  */
-for (s5500 = 0, i = 0; i < 5; i++)
-	s5500 += i;
+for (s5500 = 0, i = 0; i < 5; i++) s5500 += i;
 print "138: for (s5500 = 0, i = 0; i < 5; i++) s5500 += i;";
 vrfy(s5500 == 10,		'139: s5500 == 10');
 vrfy(i == 5,		'140: i == 5');
-for (s5500 = 0, i = 0; i < 9; i++)
-{
+for (s5500 = 0, i = 0; i < 9; i++) {
 	s5500 += i;
 }
 print "141: for (s5500 = 0, i = 0; i < 9; i++) { s5500 += i; }";
@@ -4726,7 +4723,6 @@ define test_newsyn()
 	vrfy(i == 3,			  '5509: i == 3');
 	/**/
 	{
-		local i;
 		for (s5500 = 0, i = 0; i < 11; i++)
 			s5500 += i;
 		vrfy(s5500 == 55,		  '5510: s5500 == 45');
@@ -5138,8 +5134,6 @@ print '156: parsed test_size()';
 /*
  * test_assign - test assignment of constants and variables
  */
-global A, B;	/* A, B for "constants" */
-print '157: global A, B';
 global X5800, Y5800;	/* X5800, Y5800 for "variables" */
 print '158: global X5800, Y5800';
 obj xy5800 {x, y};
@@ -7818,7 +7812,27 @@ read -once "test8500";
 print;
 print '8600: Starting test of up to 1024 args'
 read -once "test8600";
-/* 86xx: Ending test of up to 1024 args is printed by test8600.cal */
+/* 860x: Ending test of up to 1024 args is printed by test8600.cal */
+
+
+/*
+ * dupvar_warn and redecl_warn testing
+ */
+print;
+print '8650: Starting test of dupvar_warn and redecl_warn config parameters';
+vrfy(config("redecl_warn",0),	  '8651: config("redecl_warn",0)');
+vrfy(config("dupvar_warn",0),	  '8652: config("dupvar_warn",0)');
+vrfy(u_glob == 6,		  '8653: u_glob == 6');
+global u_glob = 555;
+print 				  '8654: reclare u_glob';
+vrfy(u_glob == 555,		  '8655: u_glob == 555');
+define func_8650(u_glob) { local u_glob; return u_glob; }
+print				  '8656: u_glob as both local and parameter';
+define func_8650a(u_glob) { static u_glob; return u_glob; }
+print				  '8657: u_glob as both static and parameter';
+vrfy(config("redecl_warn",1)==0,  '8658: config("redecl_warn",1)==0');
+vrfy(config("dupvar_warn",1)==0,  '8659: config("dupvar_warn",1)==0');
+/* 865x: Ending test of up to 1024 args is printed by test8600.cal */
 
 
 /*
@@ -7826,6 +7840,7 @@ read -once "test8600";
  *
  * We use the dotest driver to evaluate test-97xx data files.
  */
+print;
 print '8700: Starting dotest runs'
 print '8701: read -once "dotest"';
 read -once "dotest";
@@ -7835,6 +7850,7 @@ vrfy(dotest("set8700.line", 8703) == 0,
      '8703: dotest("set8700.line", 8703) == 0');
 /* 87xx: Ending dotest runs is printed by set8700.test */
 
+
 /*
  * read various calc resource files
  *
diff --git a/cal/set8700.line b/cal/set8700.line
index 0ec709c..dcf2f90 100644
--- a/cal/set8700.line
+++ b/cal/set8700.line
@@ -17,8 +17,8 @@
 ## received a copy with calc; if not, write to Free Software Foundation, Inc.
 ## 59 Temple Place, Suite 330, Boston, MA  02111-1307, USA.
 ##
-## @(#) $Revision: 29.1 $
-## @(#) $Id: set8700.line,v 29.1 2006/05/20 19:35:33 chongo Exp $
+## @(#) $Revision: 29.2 $
+## @(#) $Id: set8700.line,v 29.2 2006/06/20 09:29:16 chongo Exp $
 ## @(#) $Source: /usr/local/src/cmd/calc/cal/RCS/set8700.line,v $
 ##
 ## Under source code control:	2006/05/20 14:10:11
@@ -143,7 +143,7 @@ a #= 4, a == 1
 
 ## Binary # operator not defined for strings
 
-global set8700_A; protect(set8700_A) == 0
+protect(set8700_A) == 0
 ## Testing with one lvalue
 isnull(protect(set8700_A,65))
 protect(set8700_A) == 65
@@ -302,7 +302,7 @@ protect(set8700_B,0), set8700_B = set8700_getA1(), protect(set8700_B) == 1024
 protect(set8700_B,0), set8700_B = set8700_getA2(), protect(set8700_B) == 1024
 set8700_B = set8700_getvar(), protect(set8700_B) == 1024 + 256
 
-global set8700_x, set8700_y; set8700_x = 7,  protect(set8700_x) == 0
+set8700_x = 7,  protect(set8700_x) == 0
 protect(7,2) == error(10234)
 protect(set8700_x,2.5) == error(10235)
 protect(set8700_x,"abc") == error(10235)
@@ -322,7 +322,6 @@ set8700_x++ == error(10385)
 set8700_x == 7
 set8700_x-- == error(10388)
 
-global set8700_A, set8700_B; 1
 protect(set8700_A,0), protect(set8700_A,16), 1
 set8700_A = "abcdef", protect(set8700_A) == 16		## No copy to set8700_A
 protect(set8700_B,0), set8700_B = "xyz", protect(set8700_B) == 0
diff --git a/cal/test2700.cal b/cal/test2700.cal
index 8ecfc7e..be9a3aa 100644
--- a/cal/test2700.cal
+++ b/cal/test2700.cal
@@ -19,8 +19,8 @@
  * received a copy with calc; if not, write to Free Software Foundation, Inc.
  * 59 Temple Place, Suite 330, Boston, MA  02111-1307, USA.
  *
- * @(#) $Revision: 29.2 $
- * @(#) $Id: test2700.cal,v 29.2 2000/06/07 14:02:25 chongo Exp $
+ * @(#) $Revision: 29.3 $
+ * @(#) $Id: test2700.cal,v 29.3 2006/06/20 09:29:16 chongo Exp $
  * @(#) $Source: /usr/local/src/cmd/calc/cal/RCS/test2700.cal,v $
  *
  * Under source code control:	1995/11/01 22:52:25
@@ -41,8 +41,7 @@
  */
 
 
-global defaultverbose = 1;
-global err;
+defaultverbose = 1;
 
 define mknonnegreal() {
 	switch(rand(8)) {
diff --git a/cal/test3300.cal b/cal/test3300.cal
index 2e8b821..da90c73 100644
--- a/cal/test3300.cal
+++ b/cal/test3300.cal
@@ -19,8 +19,8 @@
  * received a copy with calc; if not, write to Free Software Foundation, Inc.
  * 59 Temple Place, Suite 330, Boston, MA  02111-1307, USA.
  *
- * @(#) $Revision: 29.2 $
- * @(#) $Id: test3300.cal,v 29.2 2000/06/07 14:02:25 chongo Exp $
+ * @(#) $Revision: 29.3 $
+ * @(#) $Id: test3300.cal,v 29.3 2006/06/20 09:29:16 chongo Exp $
  * @(#) $Source: /usr/local/src/cmd/calc/cal/RCS/test3300.cal,v $
  *
  * Under source code control:	1995/12/02 04:27:41
@@ -30,8 +30,7 @@
  */
 
 
-global defaultverbose = 1;	/* default verbose value */
-global err;
+defaultverbose = 1;	/* default verbose value */
 
 define testi(str, n, N, verbose)
 {
diff --git a/cal/test3400.cal b/cal/test3400.cal
index 534f168..a1c6207 100644
--- a/cal/test3400.cal
+++ b/cal/test3400.cal
@@ -19,8 +19,8 @@
  * received a copy with calc; if not, write to Free Software Foundation, Inc.
  * 59 Temple Place, Suite 330, Boston, MA  02111-1307, USA.
  *
- * @(#) $Revision: 29.2 $
- * @(#) $Id: test3400.cal,v 29.2 2000/06/07 14:02:25 chongo Exp $
+ * @(#) $Revision: 29.3 $
+ * @(#) $Id: test3400.cal,v 29.3 2006/06/20 09:29:16 chongo Exp $
  * @(#) $Source: /usr/local/src/cmd/calc/cal/RCS/test3400.cal,v $
  *
  * Under source code control:	1995/12/02 05:20:11
@@ -54,8 +54,7 @@
  */
 
 
-global defaultverbose = 1;	/* default verbose value */
-global err;
+defaultverbose = 1;	/* default verbose value */
 
 global pi1k = pi(1e-1000);
 
diff --git a/cal/test3500.cal b/cal/test3500.cal
index 270c945..337e1e6 100644
--- a/cal/test3500.cal
+++ b/cal/test3500.cal
@@ -19,8 +19,8 @@
  * received a copy with calc; if not, write to Free Software Foundation, Inc.
  * 59 Temple Place, Suite 330, Boston, MA  02111-1307, USA.
  *
- * @(#) $Revision: 29.2 $
- * @(#) $Id: test3500.cal,v 29.2 2000/06/07 14:02:25 chongo Exp $
+ * @(#) $Revision: 29.3 $
+ * @(#) $Id: test3500.cal,v 29.3 2006/06/20 09:29:16 chongo Exp $
  * @(#) $Source: /usr/local/src/cmd/calc/cal/RCS/test3500.cal,v $
  *
  * Under source code control:	1995/12/18 22:50:46
@@ -53,8 +53,7 @@
  */
 
 
-global defaultverbose = 1;	/* default verbose value */
-global err;
+defaultverbose = 1;	/* default verbose value */
 
 define testfrem(x,y,verbose)
 {
diff --git a/cal/test4000.cal b/cal/test4000.cal
index a4c5d6e..8be7fe5 100644
--- a/cal/test4000.cal
+++ b/cal/test4000.cal
@@ -19,8 +19,8 @@
  * received a copy with calc; if not, write to Free Software Foundation, Inc.
  * 59 Temple Place, Suite 330, Boston, MA  02111-1307, USA.
  *
- * @(#) $Revision: 29.2 $
- * @(#) $Id: test4000.cal,v 29.2 2000/06/07 14:02:25 chongo Exp $
+ * @(#) $Revision: 29.3 $
+ * @(#) $Id: test4000.cal,v 29.3 2006/06/20 09:29:16 chongo Exp $
  * @(#) $Source: /usr/local/src/cmd/calc/cal/RCS/test4000.cal,v $
  *
  * Under source code control:	1996/03/13 02:38:45
@@ -75,8 +75,7 @@
  */
 
 
-global defaultverbose = 1;	/* default verbose value */
-global err;
+defaultverbose = 1;	/* default verbose value */
 
 /*
  * test defaults
diff --git a/cal/test4100.cal b/cal/test4100.cal
index cc7625d..c4bbf87 100644
--- a/cal/test4100.cal
+++ b/cal/test4100.cal
@@ -19,8 +19,8 @@
  * received a copy with calc; if not, write to Free Software Foundation, Inc.
  * 59 Temple Place, Suite 330, Boston, MA  02111-1307, USA.
  *
- * @(#) $Revision: 29.3 $
- * @(#) $Id: test4100.cal,v 29.3 2006/06/10 20:19:20 chongo Exp $
+ * @(#) $Revision: 29.4 $
+ * @(#) $Id: test4100.cal,v 29.4 2006/06/20 09:29:16 chongo Exp $
  * @(#) $Source: /usr/local/src/cmd/calc/cal/RCS/test4100.cal,v $
  *
  * Under source code control:	1996/03/13 03:53:22
@@ -70,18 +70,16 @@
  */
 
 
-global defaultverbose = 1;	/* default verbose value */
-global err;
+defaultverbose = 1;	/* default verbose value */
 
 /*
  * test defaults
  */
-global K1 = 2^17;
-global K2 = 2^12;
-global BASEB = 16;
-global BASE = 2^BASEB;
+global test4100_K1 = 2^17;
+global test4100_K2 = 2^12;
+global test4100_BASE = 2^config("baseb");
 
-define rlen_4100(N) = rand(BASE^(N-1), BASE^N);
+define rlen_4100(N) = rand(test4100_BASE^(N-1), test4100_BASE^N);
 
 define olen(N)
 {
@@ -234,7 +232,7 @@ define times(str,N,n,verbose)
 	m = olen(N);
 	m2 = m^2;
 	if (isnull(n)) {
-		n = ceil(K1/power(N,1.585));
+		n = ceil(test4100_K1/power(N,1.585));
 		if (verbose > 1)
 			printf("n = %d\n", n);
 	}
@@ -308,7 +306,7 @@ define powtimes(str, N1, N2, n, verbose)
 		N2 = 1;
 
 	if (isnull(n)) {
-		n = ceil(K2/power(N1, 1.585)/N2);
+		n = ceil(test4100_K2/power(N1, 1.585)/N2);
 		printf ("n  = %d\n", n);
 	}
 	mat A[n];
@@ -408,7 +406,7 @@ define inittimes(str,N,n,verbose)
 	}
 	m = 0;
 	if (isnull(n)) {
-		n = ceil(K1/N^2);
+		n = ceil(test4100_K1/N^2);
 		if (verbose > 1) {
 			printf ("n = %d\n", n);
 		}
diff --git a/cal/test4600.cal b/cal/test4600.cal
index 400d119..032e94e 100644
--- a/cal/test4600.cal
+++ b/cal/test4600.cal
@@ -19,8 +19,8 @@
  * received a copy with calc; if not, write to Free Software Foundation, Inc.
  * 59 Temple Place, Suite 330, Boston, MA  02111-1307, USA.
  *
- * @(#) $Revision: 29.4 $
- * @(#) $Id: test4600.cal,v 29.4 2001/04/10 22:09:02 chongo Exp $
+ * @(#) $Revision: 29.5 $
+ * @(#) $Id: test4600.cal,v 29.5 2006/06/20 09:29:16 chongo Exp $
  * @(#) $Source: /usr/local/src/cmd/calc/cal/RCS/test4600.cal,v $
  *
  * Under source code control:	1996/07/02 20:04:40
@@ -30,8 +30,7 @@
  */
 
 
-global defaultverbose = 1		/* default verbose value */
-global err;
+defaultverbose = 1;	/* default verbose value */
 
 /*
  * test globals
diff --git a/cal/test5100.cal b/cal/test5100.cal
index d11ee00..d3790ad 100644
--- a/cal/test5100.cal
+++ b/cal/test5100.cal
@@ -19,8 +19,8 @@
  * received a copy with calc; if not, write to Free Software Foundation, Inc.
  * 59 Temple Place, Suite 330, Boston, MA  02111-1307, USA.
  *
- * @(#) $Revision: 29.2 $
- * @(#) $Id: test5100.cal,v 29.2 2000/06/07 14:02:25 chongo Exp $
+ * @(#) $Revision: 29.3 $
+ * @(#) $Id: test5100.cal,v 29.3 2006/06/20 09:29:16 chongo Exp $
  * @(#) $Source: /usr/local/src/cmd/calc/cal/RCS/test5100.cal,v $
  *
  * Under source code control:	1996/12/02 23:57:10
@@ -30,8 +30,7 @@
  */
 
 
-global defaultverbose = 1;	/* default verbose value */
-global err;
+defaultverbose = 1;	/* default verbose value */
 
 /*
  * We test the new code generator declaration scope and order.
diff --git a/cal/test5200.cal b/cal/test5200.cal
index d649ecc..f3aaa96 100644
--- a/cal/test5200.cal
+++ b/cal/test5200.cal
@@ -19,8 +19,8 @@
  * received a copy with calc; if not, write to Free Software Foundation, Inc.
  * 59 Temple Place, Suite 330, Boston, MA  02111-1307, USA.
  *
- * @(#) $Revision: 29.2 $
- * @(#) $Id: test5200.cal,v 29.2 2000/06/07 14:02:25 chongo Exp $
+ * @(#) $Revision: 29.3 $
+ * @(#) $Id: test5200.cal,v 29.3 2006/06/20 09:29:16 chongo Exp $
  * @(#) $Source: /usr/local/src/cmd/calc/cal/RCS/test5200.cal,v $
  *
  * Under source code control:	1997/02/07 02:48:10
@@ -30,8 +30,7 @@
  */
 
 
-global defaultverbose = 1;	/* default verbose value */
-global err;
+defaultverbose = 1;	/* default verbose value */
 
 /*
  * test the fix of a global/static bug
diff --git a/codegen.c b/codegen.c
index d11a771..e9c377a 100644
--- a/codegen.c
+++ b/codegen.c
@@ -19,8 +19,8 @@
  * received a copy with calc; if not, write to Free Software Foundation, Inc.
  * 59 Temple Place, Suite 330, Boston, MA  02111-1307, USA.
  *
- * @(#) $Revision: 29.20 $
- * @(#) $Id: codegen.c,v 29.20 2006/06/11 07:25:14 chongo Exp $
+ * @(#) $Revision: 29.21 $
+ * @(#) $Id: codegen.c,v 29.21 2006/06/20 10:28:06 chongo Exp $
  * @(#) $Source: /usr/local/src/cmd/calc/RCS/codegen.c,v $
  *
  * Under source code control:	1990/02/15 01:48:13
@@ -136,10 +136,6 @@ getcommands(BOOL toplevel)
 			getfunction();
 			break;
 
-		case T_UNDEFINE:
-			ungetfunction();
-			break;
-
 		case T_EOF:
 			if (!toplevel)
 				exitfilescope();
@@ -306,9 +302,8 @@ ungetfunction(void)
 			name = tokensymbol();
 			type = getbuiltinfunc(name);
 			if (type >= 0) {
-				errorcount--;
-				scanerror(T_NULL,
-	 "Attempt to undefine the builtin function \"%s\"", name);
+				warning(
+			"Cannot undefine builtin function \"%s\"", name);
 			continue;
 			}
 			rmuserfunc(name);
@@ -316,6 +311,16 @@ ungetfunction(void)
 		case T_MULT:
 			rmalluserfunc();
 			continue;
+		case T_STATIC:
+			if (gettoken() != T_SYMBOL) {
+				scanerror(T_SEMICOLON,
+			 "Non-identifier following \"undefine static\"");
+				return;
+			}
+			name = tokensymbol();
+			endscope(name, FALSE);
+			continue;
+
 		case T_NEWLINE:
 		case T_SEMICOLON:
 		case T_EOF:
@@ -634,6 +639,10 @@ getstatement(LABEL *contlabel, LABEL *breaklabel, LABEL *nextcaselabel, LABEL *d
 		(void) getdeclarations(SYM_LOCAL);
 		break;
 
+	case T_UNDEFINE:
+		ungetfunction();
+		break;
+
 	case T_RIGHTBRACE:
 		scanerror(T_NULL, "Extraneous right brace");
 		return;
@@ -799,10 +808,10 @@ getstatement(LABEL *contlabel, LABEL *breaklabel, LABEL *nextcaselabel, LABEL *d
 		setlabel(&label3);
 		if (contlabel == NULL_LABEL)
 			contlabel = &label3;
+		(void) tokenmode(oldmode);
 		getstatement(contlabel, breaklabel, NULL_LABEL, NULL_LABEL);
 		addoplabel(OP_JUMP, contlabel);
 		setlabel(breaklabel);
-		(void) tokenmode(oldmode);
 		return;
 
 	case T_WHILE:
@@ -811,6 +820,7 @@ getstatement(LABEL *contlabel, LABEL *breaklabel, LABEL *nextcaselabel, LABEL *d
 		clearlabel(contlabel);
 		setlabel(contlabel);
 		getcondition();
+		(void) tokenmode(oldmode);
 		if (gettoken() != T_SEMICOLON) {
 			breaklabel = &label2;
 			clearlabel(breaklabel);
@@ -823,7 +833,6 @@ getstatement(LABEL *contlabel, LABEL *breaklabel, LABEL *nextcaselabel, LABEL *d
 		} else {
 			addoplabel(OP_JUMPNZ, contlabel);
 		}
-		(void) tokenmode(oldmode);
 		return;
 
 	case T_DO:
@@ -2124,7 +2133,8 @@ getterm(void)
 
 	case T_GLOBAL:
 		if (gettoken() != T_SYMBOL) {
-			scanerror(T_NULL, "Global id expected");
+			scanerror(T_NULL,
+				 "No identifier after global specifier");
 			break;
 		}
 		rescantoken();
@@ -2133,19 +2143,30 @@ getterm(void)
 
 	case T_LOCAL:
 		if (gettoken() != T_SYMBOL) {
-			scanerror(T_NULL, "Local id expected");
+			scanerror(T_NULL,
+				 "No identifier after local specifier");
 			break;
 		}
 		rescantoken();
 		type = getidexpr(TRUE, T_LOCAL);
 		break;
 
+	case T_STATIC:
+		if (gettoken() != T_SYMBOL) {
+			scanerror(T_NULL,
+				 "No identifier after static specifier");
+			break;
+		}
+		rescantoken();
+		type = getidexpr(TRUE, T_STATIC);
+		break;
+
 	case T_LEFTBRACKET:
-		scanerror(T_NULL, "Bad index usage");
+		scanerror(T_NULL, "Left bracket with no preceding lvalue");
 		break;
 
 	case T_PERIOD:
-		scanerror(T_NULL, "Bad element reference");
+		scanerror(T_NULL, "Period with no preceding lvalue");
 		break;
 
 	default:
@@ -2207,7 +2228,8 @@ getidexpr(BOOL okmat, int autodef)
 		type = 0;
 		break;
 	case T_ASSIGN:
-		if (autodef != T_GLOBAL && autodef != T_LOCAL)
+		if (autodef != T_GLOBAL && autodef != T_LOCAL &&
+				autodef != T_STATIC)
 			autodef = 1;
 		/* fall into default case */
 	default:
@@ -2408,22 +2430,11 @@ getshowstatement(void)
 				  "stri\000"
 				  "lite\000"
 				  "opco\000", name);
-		if (arg == 19) {
-			if (gettoken() != T_SYMBOL) {
-				rescantoken();
-				scanerror(T_SEMICOLON,
-					  "Function name expected");
-				return;
-			}
-			index = adduserfunc(tokensymbol());
-			addopone(OP_SHOW, index + 19);
-			return;
-		}
-		if (arg > 0)
-			addopone(OP_SHOW, arg);
-		else
-			printf("Unknown SHOW parameter ignored\n");
-		return;
+		break;
+	case T_GLOBAL:
+		arg = 13; break;
+	case T_STATIC:
+		arg = 14; break;
 	default:
 		printf("SHOW command to be followed by at least ");
 		printf("four letters of one of:\n");
@@ -2438,6 +2449,21 @@ getshowstatement(void)
 		return;
 
 	}
+	if (arg == 19) {
+		if (gettoken() != T_SYMBOL) {
+			rescantoken();
+			scanerror(T_SEMICOLON,
+				  "Function name expected for show statement");
+			return;
+		}
+		index = adduserfunc(tokensymbol());
+		addopone(OP_SHOW, index + 19);
+		return;
+	}
+	if (arg > 0)
+		addopone(OP_SHOW, arg);
+	else
+		warning("Unknown parameter for show statement");
 }
 
 
@@ -2556,8 +2582,9 @@ getid(char *buf)
  * Define a symbol name to be of the specified symbol type.  The scope
  * of a static variable with the same name is terminated if symtype is
  * global or if symtype is static and the old variable is at the same
- * level.  A scan error occurs if the name is already in use in an
- * incompatible manner.
+ * level.  Warnings are issued when a global or local variable is
+ * redeclared and when in the same body the variable will be accessible only
+ ^ with the appropriate specfier.
  */
 static void
 definesymbol(char *name, int symtype)
@@ -2566,25 +2593,48 @@ definesymbol(char *name, int symtype)
 	case SYM_STATIC:
 		if (symtype == SYM_GLOBAL || symtype == SYM_STATIC)
 			endscope(name, symtype == SYM_GLOBAL);
-		/*FALLTHRU*/
-	case SYM_UNDEFINED:
+		break;
 	case SYM_GLOBAL:
-		if (symtype == SYM_LOCAL)
-			(void) addlocal(name);
-		else
-			(void) addglobal(name, (symtype == SYM_STATIC));
+		if (symtype == SYM_GLOBAL && conf->redecl_warn) {
+			warning("redeclaraion of global \"%s\"",
+				name);
+			return;
+		}
 		break;
 
 	case SYM_LOCAL:
-		if (symtype == SYM_LOCAL)
+		if (symtype == SYM_LOCAL && conf->redecl_warn) {
+			warning("redeclaraion of local \"%s\"",
+				name);
 			return;
-		/*FALLTHRU*/
+		}
+		if (symtype == SYM_GLOBAL && conf->dupvar_warn) {
+			warning("both local and global \"%s\" defined", name);
+			break;
+		}
+		if (conf->dupvar_warn) {
+			warning("both local and static \"%s\" defined", name);
+		}
+		break;
 	case SYM_PARAM:
-		scanerror(T_COMMA,
-			  "Variable \"%s\" is already defined", name);
-		return;
+		if (symtype == SYM_LOCAL && conf->dupvar_warn) {
+			warning("both local and parameter \"%s\" defined",
+				name);
+			break;
+		}
+		if (symtype == SYM_GLOBAL && conf->dupvar_warn) {
+			warning("both global and parameter \"%s\" defined",
+				name);
+			break;
+		}
+		if (conf->dupvar_warn) {
+			warning("both static and parameter \"%s\" defined", name);
+		}
 	}
-
+	if (symtype == SYM_LOCAL)
+		(void) addlocal(name);
+	else
+		(void) addglobal(name, (symtype == SYM_STATIC));
 }
 
 
@@ -2602,21 +2652,28 @@ definesymbol(char *name, int symtype)
 static void
 usesymbol(char *name, int autodef)
 {
+	int type;
 
+	type = symboltype(name);
 	if (autodef == T_GLOBAL) {
-			addopptr(OP_GLOBALADDR, (char *) addglobal(name, FALSE));
-			return;
+		if (type == SYM_GLOBAL) {
+			warning("Unnecessary global specifier");
+		}
+		addopptr(OP_GLOBALADDR, (char *) addglobal(name, FALSE));
+		return;
+	}
+	if (autodef == T_STATIC) {
+		addopptr(OP_GLOBALADDR, (char *) addglobal(name, TRUE));
+		return;
 	}
 	if (autodef == T_LOCAL) {
-			if (symboltype(name) == SYM_PARAM) {
-				scanerror(T_COMMA,
-				  "Variable \"%s\" is already defined", name);
-				return;
-			}
-			addopone(OP_LOCALADDR, addlocal(name));
-			return;
+		if (type == SYM_LOCAL) {
+			warning("Unnecessary local specifier");
+		}
+		addopone(OP_LOCALADDR, addlocal(name));
+		return;
 	}
-	switch (symboltype(name)) {
+	switch (type) {
 	case SYM_LOCAL:
 		addopone(OP_LOCALADDR, (long) findlocal(name));
 		return;
diff --git a/config.c b/config.c
index e746cf2..37d6d00 100644
--- a/config.c
+++ b/config.c
@@ -19,8 +19,8 @@
  * received a copy with calc; if not, write to Free Software Foundation, Inc.
  * 59 Temple Place, Suite 330, Boston, MA  02111-1307, USA.
  *
- * @(#) $Revision: 29.20 $
- * @(#) $Id: config.c,v 29.20 2006/06/11 00:08:56 chongo Exp $
+ * @(#) $Revision: 29.21 $
+ * @(#) $Id: config.c,v 29.21 2006/06/20 10:25:45 chongo Exp $
  * @(#) $Source: /usr/local/src/cmd/calc/RCS/config.c,v $
  *
  * Under source code control:	1991/07/20 00:21:56
@@ -98,6 +98,8 @@ NAMETYPE configs[] = {
 	{"allow_custom",	CONFIG_ALLOW_CUSTOM},
 	{"version",	CONFIG_VERSION},
 	{"baseb",	CONFIG_BASEB},
+	{"redecl_warn",	CONFIG_REDECL_WARN},
+	{"dupvar_warn",	CONFIG_DUPVAR_WARN},
 	{NULL,		0}
 };
 
@@ -162,6 +164,8 @@ CONFIG oldstd = {	/* backward compatible standard configuration */
 	&allow_custom,		/* *TRUE=> custom functions are enabled */
 	NULL,			/* version */
 	BASEB,			/* base for calculations */
+	TRUE,			/* warn when redeclaring */
+	TRUE,			/* warn when variable names collide */
 };
 CONFIG newstd = {	/* new non-backward compatible configuration */
 	MODE_INITIAL,		/* current output mode */
@@ -220,6 +224,8 @@ CONFIG newstd = {	/* new non-backward compatible configuration */
 	&allow_custom,		/* *TRUE=> custom functions are enabled */
 	NULL,			/* version */
 	BASEB,			/* base for calculations */
+	TRUE,			/* warn when redeclaring */
+	TRUE,			/* warn when variable names collide */
 };
 CONFIG *conf = NULL;	/* loaded in at startup - current configuration */
 
@@ -906,6 +912,34 @@ setconfig(int type, VALUE *vp)
 		math_error("The baseb config parameter is read-only");
 		/*NOTREACHED*/
 
+	case CONFIG_REDECL_WARN:
+		if (vp->v_type == V_NUM) {
+			q = vp->v_num;
+			conf->redecl_warn = !qiszero(q);
+		} else if (vp->v_type == V_STR) {
+			temp = lookup_long(truth, vp->v_str->s_str);
+			if (temp < 0) {
+				math_error("Illegal truth value for redecl_warn");
+				/*NOTREACHED*/
+			}
+			conf->redecl_warn = (int)temp;
+		}
+		break;
+
+	case CONFIG_DUPVAR_WARN:
+		if (vp->v_type == V_NUM) {
+			q = vp->v_num;
+			conf->dupvar_warn = !qiszero(q);
+		} else if (vp->v_type == V_STR) {
+			temp = lookup_long(truth, vp->v_str->s_str);
+			if (temp < 0) {
+				math_error("Illegal truth value for dupvar_warn");
+				/*NOTREACHED*/
+			}
+			conf->dupvar_warn = (int)temp;
+		}
+		break;
+
 	default:
 		math_error("Setting illegal config parameter");
 		/*NOTREACHED*/
@@ -1287,6 +1321,14 @@ config_value(CONFIG *cfg, int type, VALUE *vp)
 		i = BASEB;
 		break;
 
+	case CONFIG_REDECL_WARN:
+		i = (cfg->redecl_warn ? 1 : 0);
+		break;
+
+	case CONFIG_DUPVAR_WARN:
+		i = (cfg->dupvar_warn ? 1 : 0);
+		break;
+
 	default:
 		math_error("Getting illegal CONFIG element");
 		/*NOTREACHED*/
diff --git a/config.h b/config.h
index 71aabca..de4fde2 100644
--- a/config.h
+++ b/config.h
@@ -19,8 +19,8 @@
  * received a copy with calc; if not, write to Free Software Foundation, Inc.
  * 59 Temple Place, Suite 330, Boston, MA  02111-1307, USA.
  *
- * @(#) $Revision: 29.18 $
- * @(#) $Id: config.h,v 29.18 2006/06/06 07:17:02 chongo Exp $
+ * @(#) $Revision: 29.19 $
+ * @(#) $Id: config.h,v 29.19 2006/06/20 10:25:45 chongo Exp $
  * @(#) $Source: /usr/local/src/cmd/calc/RCS/config.h,v $
  *
  * Under source code control:	1995/11/01 22:20:17
@@ -95,6 +95,8 @@
 #define CONFIG_COMPILE_CUSTOM	41
 #define CONFIG_ALLOW_CUSTOM	42
 #define CONFIG_BASEB	43
+#define CONFIG_REDECL_WARN	44
+#define CONFIG_DUPVAR_WARN	45
 
 
 /*
@@ -164,6 +166,8 @@ struct config {
 	BOOL *allow_custom;	/* ptr to if custom functions are allowed */
 	char *version;		/* calc version string */
 	int baseb;		/* base for calculations */
+	BOOL redecl_warn;	/* TRUE => warn of redeclating variables */
+	BOOL dupvar_warn;	/* TRUE => warn of var name collisions */
 };
 typedef struct config CONFIG;
 
diff --git a/hash.c b/hash.c
index 6f840ff..2bdbd93 100644
--- a/hash.c
+++ b/hash.c
@@ -17,8 +17,8 @@
  * received a copy with calc; if not, write to Free Software Foundation, Inc.
  * 59 Temple Place, Suite 330, Boston, MA  02111-1307, USA.
  *
- * @(#) $Revision: 29.9 $
- * @(#) $Id: hash.c,v 29.9 2006/06/06 07:17:02 chongo Exp $
+ * @(#) $Revision: 29.10 $
+ * @(#) $Id: hash.c,v 29.10 2006/06/20 10:25:45 chongo Exp $
  * @(#) $Source: /usr/local/src/cmd/calc/RCS/hash.c,v $
  *
  * Under source code control:	1995/11/23 05:13:11
@@ -996,6 +996,8 @@ hash_value(int type, void *v, HASH *state)
 		}
 		state = hash_str(type, value->v_config->version, state);
 		state = hash_int(type, value->v_config->baseb, state);
+		state = hash_bool(type, value->v_config->redecl_warn, state);
+		state = hash_bool(type, value->v_config->dupvar_warn, state);
 		break;
 
 	case V_HASH:
diff --git a/help/config b/help/config
index c9ca850..06cd3ba 100644
--- a/help/config
+++ b/help/config
@@ -50,13 +50,13 @@ DESCRIPTION
 	    "prompt"		default interactive prompt
 	    "more"		default interactive multi-line input prompt
 	    "blkmaxprint"	number of block octets to print, 0 means all
-	    "blkverbose"	TRUE=>print all lines, FALSE=>skip duplicates
+	    "blkverbose"	TRUE => print all lines, FALSE=>skip duplicates
 	    "blkbase"		block output base
 	    "blkfmt"		block output format
 	    "calc_debug"	controls internal calc debug information
 	    "resource_debug"	controls resource file debug information
 	    "user_debug"	for user defined debug information
-	    "verbose_quit"	TRUE=>print message on empty quit or abort
+	    "verbose_quit"	TRUE => print message on empty quit or abort
 	    "ctrl_d"		The interactive meaning of ^D (Control D)
 	    "program"		Read-only calc program or shell script path
 	    "basename"		Read-only basename of the program value
@@ -66,6 +66,8 @@ DESCRIPTION
 	    "allow_custom"	TRUE=>custom functions are enabled
 	    "version"		Read-only calc version
 	    "baseb"		bits in calculation base, a read-only value
+	    "redecl_warn"	TRUE => warn when redeclaring
+	    "dupvar_warn"	TRUE => warn when variable names collide
 
     The "all" config value allows one to save/restore the configuration
     set of values.  The return of:
@@ -279,14 +281,14 @@ DESCRIPTION
     established on a 1.8GHz AMD 32-bit CPU of ~3406 BogoMIPS when
     the two algorithms are about equal in speed.  For that CPU test,
     config("baseb") was 32.  This means that by default numbers up to
-    (3388*32)+31 = 108447 bits in length (< 32645 decinal digits) use
+    (3388*32)+31 = 108447 bits in length (< 32645 decimal digits) use
     the 1st algorithm, for squaring.
 
     The default value for config("mul2") is 1780.  This default was
     established on a 1.8GHz AMD 32-bit CPU of ~3406 BogoMIPS when
     the two algorithms are about equal in speed.  For that CPU test,
     config("baseb") was 32.  This means that by default numbers up to
-    (1779*32)+31 = 56927 bits in length (< 17137 decinal digits) use
+    (1779*32)+31 = 56927 bits in length (< 17137 decimal digits) use
     the 1st algorithm, for multiplication.
 
     A value of zero resets the parameter back to their default values.
@@ -315,7 +317,7 @@ DESCRIPTION
     established on a 1.8GHz AMD 32-bit CPU of ~3406 BogoMIPS when
     the two algorithms are about equal in speed.  For that CPU test,
     config("baseb") was 32.  This means that by default numbers up to
-    (176*32)+31 = 5663 bits in length (< 1704 decinal digits) use the
+    (176*32)+31 = 5663 bits in length (< 1704 decimal digits) use the
     1st algorithm, for calculating powers modulo another number.
 
     A value of zero resets the parameter back to their default values.
@@ -344,7 +346,7 @@ DESCRIPTION
     established as 5/4 (the historical ratio of config("pow2") to
     config("pow2")) of the config("pow2") value.  This means that if
     config("baseb") is 32, then by default numbers up to (220*32)+31 =
-    7071 bits in length (< 2128 decinal digits) use the REDC algorithm,
+    7071 bits in length (< 2128 decimal digits) use the REDC algorithm,
     for calculating powers modulo another number.
 
     A value of zero resets the parameter back to their default values.
@@ -430,7 +432,7 @@ DESCRIPTION
 
     =-=
 
-    config("leadzero", bool)
+    config("leadzero", boolean)
 
     The "leadzero" parameter controls whether or not a 0 is printed
     before the decimal point in non-zero fractions with absolute value
@@ -439,7 +441,7 @@ DESCRIPTION
 
     =-=
 
-    config("fullzero", bool)
+    config("fullzero", boolean)
 
     The "fullzero" parameter controls whether or not in decimal floating-
     point printing, the digits are padded with zeros to reach the
@@ -490,7 +492,7 @@ DESCRIPTION
 
     =-=
 
-    config("blkverbose", bool)
+    config("blkverbose", boolean)
 
     The "blkverbose" determines if all lines, including duplicates
     should be printed.	If TRUE, then all lines are printed.  If false,
@@ -656,7 +658,7 @@ DESCRIPTION
 
     =-=
 
-    config("verbose_quit", bool)
+    config("verbose_quit", boolean)
 
     The "verbose_quit" controls the print of the message:
 
@@ -835,6 +837,31 @@ DESCRIPTION
 
     This config parameter is read-only and cannot be set.
 
+    =-=
+
+    config("redecl_warn", boolean)
+
+    Config("redecl_warn") controls whether or not a warning is issued
+    when redeclaring variables.
+
+    The initial "redecl_warn" value is 1.
+
+    =-=
+
+    config("dupvar_warn", boolean)
+
+    Config("dupvar_warn") controls whether or not a warning is issued
+    when a variable name collides with an exist name of a higher scope.
+    Examples of collisions are when:
+
+    	* both local and static variables have the same name
+    	* both local and global variables have the same name
+    	* both function parameter and local variables have the same name
+    	* both function parameter and global variables have the same name
+
+    The initial "redecl_warn" value is 1.
+
+
 EXAMPLE
     ; current_cfg = config("all");
     ; config("tilde", off),;
@@ -893,6 +920,8 @@ EXAMPLE
 	allow_custom    0
 	version         "2.12.0"
 	baseb		32
+	redecl_warn	1
+	dupvar_warn	1
 
     ; display()
 	20
@@ -925,8 +954,8 @@ SEE ALSO
 ## received a copy with calc; if not, write to Free Software Foundation, Inc.
 ## 59 Temple Place, Suite 330, Boston, MA  02111-1307, USA.
 ##
-## @(#) $Revision: 29.15 $
-## @(#) $Id: config,v 29.15 2006/06/11 07:22:05 chongo Exp $
+## @(#) $Revision: 29.16 $
+## @(#) $Id: config,v 29.16 2006/06/20 10:25:00 chongo Exp $
 ## @(#) $Source: /usr/local/src/cmd/calc/help/RCS/config,v $
 ##
 ## Under source code control:	1991/07/21 04:37:17
diff --git a/quickhash.c b/quickhash.c
index acf73c9..a396746 100644
--- a/quickhash.c
+++ b/quickhash.c
@@ -17,8 +17,8 @@
  * received a copy with calc; if not, write to Free Software Foundation, Inc.
  * 59 Temple Place, Suite 330, Boston, MA  02111-1307, USA.
  *
- * @(#) $Revision: 29.10 $
- * @(#) $Id: quickhash.c,v 29.10 2006/06/06 07:17:02 chongo Exp $
+ * @(#) $Revision: 29.11 $
+ * @(#) $Id: quickhash.c,v 29.11 2006/06/20 10:25:45 chongo Exp $
  * @(#) $Source: /usr/local/src/cmd/calc/RCS/quickhash.c,v $
  *
  * Under source code control:	1995/03/04 11:34:23
@@ -488,6 +488,8 @@ config_hash(CONFIG *cfg, QCKHASH val)
 		val = fnv_strhash(cfg->version, val);
 	}
 	value = (((value>>5) | (value<<27)) ^ (USB32)cfg->baseb);
+	value = (((value>>5) | (value<<27)) ^ (USB32)cfg->redecl_warn);
+	value = (((value>>5) | (value<<27)) ^ (USB32)cfg->dupvar_warn);
 
 	/*
 	 * hash the epsilon if possible
diff --git a/symbol.c b/symbol.c
index f3bf6d2..e403271 100644
--- a/symbol.c
+++ b/symbol.c
@@ -19,8 +19,8 @@
  * received a copy with calc; if not, write to Free Software Foundation, Inc.
  * 59 Temple Place, Suite 330, Boston, MA  02111-1307, USA.
  *
- * @(#) $Revision: 29.5 $
- * @(#) $Id: symbol.c,v 29.5 2006/05/20 08:43:55 chongo Exp $
+ * @(#) $Revision: 29.6 $
+ * @(#) $Id: symbol.c,v 29.6 2006/06/20 10:28:06 chongo Exp $
  * @(#) $Source: /usr/local/src/cmd/calc/RCS/symbol.c,v $
  *
  * Under source code control:	1990/02/15 01:48:23
@@ -511,6 +511,7 @@ endscope(char *name, BOOL isglobal)
 					prevsp->g_next = sp->g_next;
 				else
 					*hp = sp->g_next;
+				continue;
 			}
 		}
 		prevsp = sp;
@@ -754,10 +755,10 @@ symboltype(char *name)
 {
 	GLOBAL *sp;
 
-	if (findlocal(name) >= 0)
-		return SYM_LOCAL;
 	if (findparam(name) >= 0)
 		return SYM_PARAM;
+	if (findlocal(name) >= 0)
+		return SYM_LOCAL;
 	sp = findglobal(name);
 	if (sp) {
 		if (sp->g_filescope == SCOPE_GLOBAL)
diff --git a/token.c b/token.c
index f1f60de..d67be8d 100644
--- a/token.c
+++ b/token.c
@@ -19,8 +19,8 @@
  * received a copy with calc; if not, write to Free Software Foundation, Inc.
  * 59 Temple Place, Suite 330, Boston, MA  02111-1307, USA.
  *
- * @(#) $Revision: 29.8 $
- * @(#) $Id: token.c,v 29.8 2006/06/03 22:47:28 chongo Exp $
+ * @(#) $Revision: 29.9 $
+ * @(#) $Id: token.c,v 29.9 2006/06/20 10:28:06 chongo Exp $
  * @(#) $Source: /usr/local/src/cmd/calc/RCS/token.c,v $
  *
  * Under source code control:	1990/02/15 01:48:25
@@ -770,3 +770,23 @@ scanerror(int skip, char *fmt, ...)
 		}
 	}
 }
+
+/*
+ * Display a warning and return to compiling
+ */
+void
+warning(char *fmt, ...)
+{
+	va_list ap;
+	char *name;		/* name of file with error */
+	char buf[MAXERROR+1];
+
+	name = inputname();
+	if (name)
+		fprintf(stderr, "\"%s\", line %ld: ", name, linenumber());
+	va_start(ap, fmt);
+	vsnprintf(buf, MAXERROR, fmt, ap);
+	va_end(ap);
+	buf[MAXERROR] = '\0';
+	fprintf(stderr, "Warning: %s\n", buf);
+}
diff --git a/token.h b/token.h
index 12d79ca..ff36cd2 100644
--- a/token.h
+++ b/token.h
@@ -17,8 +17,8 @@
  * received a copy with calc; if not, write to Free Software Foundation, Inc.
  * 59 Temple Place, Suite 330, Boston, MA  02111-1307, USA.
  *
- * @(#) $Revision: 29.4 $
- * @(#) $Id: token.h,v 29.4 2001/06/08 21:00:58 chongo Exp $
+ * @(#) $Revision: 29.5 $
+ * @(#) $Id: token.h,v 29.5 2006/06/20 10:28:06 chongo Exp $
  * @(#) $Source: /usr/local/src/cmd/calc/RCS/token.h,v $
  *
  * Under source code control:	1990/02/15 01:48:37
@@ -176,6 +176,7 @@ extern int tokenmode(int flag);
 extern int gettoken(void);
 extern void rescantoken(void);
 extern void scanerror(int, char *, ...);
+extern void warning(char *, ...);
 
 
 #endif /* !__TOKEN_H__ */
diff --git a/version.c b/version.c
index 8abb41a..b45f8d3 100644
--- a/version.c
+++ b/version.c
@@ -19,8 +19,8 @@
  * received a copy with calc; if not, write to Free Software Foundation, Inc.
  * 59 Temple Place, Suite 330, Boston, MA  02111-1307, USA.
  *
- * @(#) $Revision: 29.60 $
- * @(#) $Id: version.c,v 29.60 2006/06/11 07:52:58 chongo Exp $
+ * @(#) $Revision: 29.61 $
+ * @(#) $Id: version.c,v 29.61 2006/06/20 09:27:07 chongo Exp $
  * @(#) $Source: /usr/local/src/cmd/calc/RCS/version.c,v $
  *
  * Under source code control:	1990/05/22 11:00:58
@@ -48,7 +48,7 @@ static char *program;
 #define MAJOR_VER	2	/* major version */
 #define MINOR_VER	12	/* minor version */
 #define MAJOR_PATCH	0	/* patch level or 0 if no patch */
-#define MINOR_PATCH	3	/* test number or 0 if no minor patch */
+#define MINOR_PATCH	4	/* test number or 0 if no minor patch */
 
 
 /*