diff --git a/src/pkg/regexp/exec.go b/src/pkg/regexp/exec.go
index 3b0e3888524..d7057a191b7 100644
--- a/src/pkg/regexp/exec.go
+++ b/src/pkg/regexp/exec.go
@@ -90,15 +90,15 @@ func (m *machine) match(i input, pos int) bool {
 		m.matchcap[i] = -1
 	}
 	runq, nextq := &m.q0, &m.q1
-	rune, rune1 := endOfText, endOfText
+	r, r1 := endOfText, endOfText
 	width, width1 := 0, 0
-	rune, width = i.step(pos)
-	if rune != endOfText {
-		rune1, width1 = i.step(pos + width)
+	r, width = i.step(pos)
+	if r != endOfText {
+		r1, width1 = i.step(pos + width)
 	}
 	var flag syntax.EmptyOp
 	if pos == 0 {
-		flag = syntax.EmptyOpContext(-1, rune)
+		flag = syntax.EmptyOpContext(-1, r)
 	} else {
 		flag = i.context(pos)
 	}
@@ -112,15 +112,15 @@ func (m *machine) match(i input, pos int) bool {
 				// Have match; finished exploring alternatives.
 				break
 			}
-			if len(m.re.prefix) > 0 && rune1 != m.re.prefixRune && i.canCheckPrefix() {
+			if len(m.re.prefix) > 0 && r1 != m.re.prefixRune && i.canCheckPrefix() {
 				// Match requires literal prefix; fast search for it.
 				advance := i.index(m.re, pos)
 				if advance < 0 {
 					break
 				}
 				pos += advance
-				rune, width = i.step(pos)
-				rune1, width1 = i.step(pos + width)
+				r, width = i.step(pos)
+				r1, width1 = i.step(pos + width)
 			}
 		}
 		if !m.matched {
@@ -129,8 +129,8 @@ func (m *machine) match(i input, pos int) bool {
 			}
 			m.add(runq, uint32(m.p.Start), pos, m.matchcap, flag, nil)
 		}
-		flag = syntax.EmptyOpContext(rune, rune1)
-		m.step(runq, nextq, pos, pos+width, rune, flag)
+		flag = syntax.EmptyOpContext(r, r1)
+		m.step(runq, nextq, pos, pos+width, r, flag)
 		if width == 0 {
 			break
 		}
@@ -140,9 +140,9 @@ func (m *machine) match(i input, pos int) bool {
 			break
 		}
 		pos += width
-		rune, width = rune1, width1
-		if rune != endOfText {
-			rune1, width1 = i.step(pos + width)
+		r, width = r1, width1
+		if r != endOfText {
+			r1, width1 = i.step(pos + width)
 		}
 		runq, nextq = nextq, runq
 	}
@@ -166,7 +166,7 @@ func (m *machine) clear(q *queue) {
 // The step processes the rune c (which may be endOfText),
 // which starts at position pos and ends at nextPos.
 // nextCond gives the setting for the empty-width flags after c.
-func (m *machine) step(runq, nextq *queue, pos, nextPos, c int, nextCond syntax.EmptyOp) {
+func (m *machine) step(runq, nextq *queue, pos, nextPos int, c rune, nextCond syntax.EmptyOp) {
 	longest := m.re.longest
 	for j := 0; j < len(runq.dense); j++ {
 		d := &runq.dense[j]
diff --git a/src/pkg/regexp/regexp.go b/src/pkg/regexp/regexp.go
index 2325f6204b1..a1b7951bfe8 100644
--- a/src/pkg/regexp/regexp.go
+++ b/src/pkg/regexp/regexp.go
@@ -83,7 +83,7 @@ type Regexp struct {
 	prefix         string         // required prefix in unanchored matches
 	prefixBytes    []byte         // prefix, as a []byte
 	prefixComplete bool           // prefix is the entire regexp
-	prefixRune     int            // first rune in prefix
+	prefixRune     rune           // first rune in prefix
 	cond           syntax.EmptyOp // empty-width conditions required at start of match
 	numSubexp      int
 	longest        bool
@@ -224,13 +224,13 @@ func (re *Regexp) NumSubexp() int {
 	return re.numSubexp
 }
 
-const endOfText = -1
+const endOfText rune = -1
 
 // input abstracts different representations of the input text. It provides
 // one-character lookahead.
 type input interface {
-	step(pos int) (rune int, width int) // advance one rune
-	canCheckPrefix() bool               // can we look ahead without losing info?
+	step(pos int) (r rune, width int) // advance one rune
+	canCheckPrefix() bool             // can we look ahead without losing info?
 	hasPrefix(re *Regexp) bool
 	index(re *Regexp, pos int) int
 	context(pos int) syntax.EmptyOp
@@ -245,11 +245,11 @@ func newInputString(str string) *inputString {
 	return &inputString{str: str}
 }
 
-func (i *inputString) step(pos int) (int, int) {
+func (i *inputString) step(pos int) (rune, int) {
 	if pos < len(i.str) {
 		c := i.str[pos]
 		if c < utf8.RuneSelf {
-			return int(c), 1
+			return rune(c), 1
 		}
 		return utf8.DecodeRuneInString(i.str[pos:])
 	}
@@ -269,7 +269,7 @@ func (i *inputString) index(re *Regexp, pos int) int {
 }
 
 func (i *inputString) context(pos int) syntax.EmptyOp {
-	r1, r2 := -1, -1
+	r1, r2 := endOfText, endOfText
 	if pos > 0 && pos <= len(i.str) {
 		r1, _ = utf8.DecodeLastRuneInString(i.str[:pos])
 	}
@@ -288,11 +288,11 @@ func newInputBytes(str []byte) *inputBytes {
 	return &inputBytes{str: str}
 }
 
-func (i *inputBytes) step(pos int) (int, int) {
+func (i *inputBytes) step(pos int) (rune, int) {
 	if pos < len(i.str) {
 		c := i.str[pos]
 		if c < utf8.RuneSelf {
-			return int(c), 1
+			return rune(c), 1
 		}
 		return utf8.DecodeRune(i.str[pos:])
 	}
@@ -312,7 +312,7 @@ func (i *inputBytes) index(re *Regexp, pos int) int {
 }
 
 func (i *inputBytes) context(pos int) syntax.EmptyOp {
-	r1, r2 := -1, -1
+	r1, r2 := endOfText, endOfText
 	if pos > 0 && pos <= len(i.str) {
 		r1, _ = utf8.DecodeLastRune(i.str[:pos])
 	}
@@ -333,7 +333,7 @@ func newInputReader(r io.RuneReader) *inputReader {
 	return &inputReader{r: r}
 }
 
-func (i *inputReader) step(pos int) (int, int) {
+func (i *inputReader) step(pos int) (rune, int) {
 	if !i.atEOT && pos != i.pos {
 		return endOfText, 0
 
diff --git a/src/pkg/regexp/syntax/compile.go b/src/pkg/regexp/syntax/compile.go
index c415d39a57e..c90de3fe99d 100644
--- a/src/pkg/regexp/syntax/compile.go
+++ b/src/pkg/regexp/syntax/compile.go
@@ -91,8 +91,8 @@ func (c *compiler) init() {
 	c.inst(InstFail)
 }
 
-var anyRuneNotNL = []int{0, '\n' - 1, '\n' + 1, unicode.MaxRune}
-var anyRune = []int{0, unicode.MaxRune}
+var anyRuneNotNL = []rune{0, '\n' - 1, '\n' + 1, unicode.MaxRune}
+var anyRune = []rune{0, unicode.MaxRune}
 
 func (c *compiler) compile(re *Regexp) frag {
 	switch re.Op {
@@ -262,12 +262,12 @@ func (c *compiler) empty(op EmptyOp) frag {
 	return f
 }
 
-func (c *compiler) rune(rune []int, flags Flags) frag {
+func (c *compiler) rune(r []rune, flags Flags) frag {
 	f := c.inst(InstRune)
 	i := &c.p.Inst[f.i]
-	i.Rune = rune
+	i.Rune = r
 	flags &= FoldCase // only relevant flag is FoldCase
-	if len(rune) != 1 || unicode.SimpleFold(rune[0]) == rune[0] {
+	if len(r) != 1 || unicode.SimpleFold(r[0]) == r[0] {
 		// and sometimes not even that
 		flags &^= FoldCase
 	}
@@ -276,11 +276,11 @@ func (c *compiler) rune(rune []int, flags Flags) frag {
 
 	// Special cases for exec machine.
 	switch {
-	case flags&FoldCase == 0 && (len(rune) == 1 || len(rune) == 2 && rune[0] == rune[1]):
+	case flags&FoldCase == 0 && (len(r) == 1 || len(r) == 2 && r[0] == r[1]):
 		i.Op = InstRune1
-	case len(rune) == 2 && rune[0] == 0 && rune[1] == unicode.MaxRune:
+	case len(r) == 2 && r[0] == 0 && r[1] == unicode.MaxRune:
 		i.Op = InstRuneAny
-	case len(rune) == 4 && rune[0] == 0 && rune[1] == '\n'-1 && rune[2] == '\n'+1 && rune[3] == unicode.MaxRune:
+	case len(r) == 4 && r[0] == 0 && r[1] == '\n'-1 && r[2] == '\n'+1 && r[3] == unicode.MaxRune:
 		i.Op = InstRuneAnyNotNL
 	}
 
diff --git a/src/pkg/regexp/syntax/make_perl_groups.pl b/src/pkg/regexp/syntax/make_perl_groups.pl
index 6d1b84b1003..d024f5090e9 100755
--- a/src/pkg/regexp/syntax/make_perl_groups.pl
+++ b/src/pkg/regexp/syntax/make_perl_groups.pl
@@ -57,7 +57,7 @@ sub ComputeClass($) {
 
 sub PrintClass($$@) {
   my ($cname, $name, @ranges) = @_;
-  print "var code$cname = []int{  /* $name */\n";
+  print "var code$cname = []rune{  /* $name */\n";
   for (my $i=0; $i<@ranges; $i++) {
     my @a = @{$ranges[$i]};
     printf "\t0x%x, 0x%x,\n", $a[0], $a[1];
diff --git a/src/pkg/regexp/syntax/parse.go b/src/pkg/regexp/syntax/parse.go
index 1165db3e221..f5602628e70 100644
--- a/src/pkg/regexp/syntax/parse.go
+++ b/src/pkg/regexp/syntax/parse.go
@@ -82,7 +82,7 @@ type parser struct {
 	free        *Regexp
 	numCap      int // number of capturing groups seen
 	wholeRegexp string
-	tmpClass    []int // temporary char class work space
+	tmpClass    []rune // temporary char class work space
 }
 
 func (p *parser) newRegexp(op Op) *Regexp {
@@ -149,7 +149,7 @@ func (p *parser) push(re *Regexp) *Regexp {
 // If r >= 0 and there's a node left over, maybeConcat uses it
 // to push r with the given flags.
 // maybeConcat reports whether r was pushed.
-func (p *parser) maybeConcat(r int, flags Flags) bool {
+func (p *parser) maybeConcat(r rune, flags Flags) bool {
 	n := len(p.stack)
 	if n < 2 {
 		return false
@@ -178,7 +178,7 @@ func (p *parser) maybeConcat(r int, flags Flags) bool {
 }
 
 // newLiteral returns a new OpLiteral Regexp with the given flags
-func (p *parser) newLiteral(r int, flags Flags) *Regexp {
+func (p *parser) newLiteral(r rune, flags Flags) *Regexp {
 	re := p.newRegexp(OpLiteral)
 	re.Flags = flags
 	if flags&FoldCase != 0 {
@@ -190,7 +190,7 @@ func (p *parser) newLiteral(r int, flags Flags) *Regexp {
 }
 
 // minFoldRune returns the minimum rune fold-equivalent to r.
-func minFoldRune(r int) int {
+func minFoldRune(r rune) rune {
 	if r < minFold || r > maxFold {
 		return r
 	}
@@ -206,7 +206,7 @@ func minFoldRune(r int) int {
 
 // literal pushes a literal regexp for the rune r on the stack
 // and returns that regexp.
-func (p *parser) literal(r int) {
+func (p *parser) literal(r rune) {
 	p.push(p.newLiteral(r, p.flags))
 }
 
@@ -369,7 +369,7 @@ func (p *parser) factor(sub []*Regexp, flags Flags) []*Regexp {
 	}
 
 	// Round 1: Factor out common literal prefixes.
-	var str []int
+	var str []rune
 	var strflags Flags
 	start := 0
 	out := sub[:0]
@@ -380,7 +380,7 @@ func (p *parser) factor(sub []*Regexp, flags Flags) []*Regexp {
 		//
 		// Invariant: sub[start:i] consists of regexps that all begin
 		// with str as modified by strflags.
-		var istr []int
+		var istr []rune
 		var iflags Flags
 		if i < len(sub) {
 			istr, iflags = p.leadingString(sub[i])
@@ -543,7 +543,7 @@ func (p *parser) factor(sub []*Regexp, flags Flags) []*Regexp {
 
 // leadingString returns the leading literal string that re begins with.
 // The string refers to storage in re or its children.
-func (p *parser) leadingString(re *Regexp) ([]int, Flags) {
+func (p *parser) leadingString(re *Regexp) ([]rune, Flags) {
 	if re.Op == OpConcat && len(re.Sub) > 0 {
 		re = re.Sub[0]
 	}
@@ -639,7 +639,7 @@ func literalRegexp(s string, flags Flags) *Regexp {
 	for _, c := range s {
 		if len(re.Rune) >= cap(re.Rune) {
 			// string is too long to fit in Rune0.  let Go handle it
-			re.Rune = []int(s)
+			re.Rune = []rune(s)
 			break
 		}
 		re.Rune = append(re.Rune, c)
@@ -662,7 +662,7 @@ func Parse(s string, flags Flags) (*Regexp, os.Error) {
 	var (
 		p          parser
 		err        os.Error
-		c          int
+		c          rune
 		op         Op
 		lastRepeat string
 		min, max   int
@@ -935,7 +935,7 @@ func (p *parser) parsePerlFlags(s string) (rest string, err os.Error) {
 	}
 
 	// Non-capturing group.  Might also twiddle Perl flags.
-	var c int
+	var c rune
 	t = t[2:] // skip (?
 	flags := p.flags
 	sign := +1
@@ -1049,7 +1049,7 @@ func isCharClass(re *Regexp) bool {
 }
 
 // does re match r?
-func matchRune(re *Regexp, r int) bool {
+func matchRune(re *Regexp, r rune) bool {
 	switch re.Op {
 	case OpLiteral:
 		return len(re.Rune) == 1 && re.Rune[0] == r
@@ -1186,7 +1186,7 @@ func (p *parser) parseRightParen() os.Error {
 
 // parseEscape parses an escape sequence at the beginning of s
 // and returns the rune.
-func (p *parser) parseEscape(s string) (r int, rest string, err os.Error) {
+func (p *parser) parseEscape(s string) (r rune, rest string, err os.Error) {
 	t := s[1:]
 	if t == "" {
 		return 0, "", &Error{ErrTrailingBackslash, ""}
@@ -1221,7 +1221,7 @@ Switch:
 			if t == "" || t[0] < '0' || t[0] > '7' {
 				break
 			}
-			r = r*8 + int(t[0]) - '0'
+			r = r*8 + rune(t[0]) - '0'
 			t = t[1:]
 		}
 		return r, t, nil
@@ -1302,7 +1302,7 @@ Switch:
 
 // parseClassChar parses a character class character at the beginning of s
 // and returns it.
-func (p *parser) parseClassChar(s, wholeClass string) (r int, rest string, err os.Error) {
+func (p *parser) parseClassChar(s, wholeClass string) (r rune, rest string, err os.Error) {
 	if s == "" {
 		return 0, "", &Error{Code: ErrMissingBracket, Expr: wholeClass}
 	}
@@ -1318,13 +1318,13 @@ func (p *parser) parseClassChar(s, wholeClass string) (r int, rest string, err o
 
 type charGroup struct {
 	sign  int
-	class []int
+	class []rune
 }
 
 // parsePerlClassEscape parses a leading Perl character class escape like \d
 // from the beginning of s.  If one is present, it appends the characters to r
 // and returns the new slice r and the remainder of the string.
-func (p *parser) parsePerlClassEscape(s string, r []int) (out []int, rest string) {
+func (p *parser) parsePerlClassEscape(s string, r []rune) (out []rune, rest string) {
 	if p.flags&PerlX == 0 || len(s) < 2 || s[0] != '\\' {
 		return
 	}
@@ -1338,7 +1338,7 @@ func (p *parser) parsePerlClassEscape(s string, r []int) (out []int, rest string
 // parseNamedClass parses a leading POSIX named character class like [:alnum:]
 // from the beginning of s.  If one is present, it appends the characters to r
 // and returns the new slice r and the remainder of the string.
-func (p *parser) parseNamedClass(s string, r []int) (out []int, rest string, err os.Error) {
+func (p *parser) parseNamedClass(s string, r []rune) (out []rune, rest string, err os.Error) {
 	if len(s) < 2 || s[0] != '[' || s[1] != ':' {
 		return
 	}
@@ -1356,7 +1356,7 @@ func (p *parser) parseNamedClass(s string, r []int) (out []int, rest string, err
 	return p.appendGroup(r, g), s, nil
 }
 
-func (p *parser) appendGroup(r []int, g charGroup) []int {
+func (p *parser) appendGroup(r []rune, g charGroup) []rune {
 	if p.flags&FoldCase == 0 {
 		if g.sign < 0 {
 			r = appendNegatedClass(r, g.class)
@@ -1401,7 +1401,7 @@ func unicodeTable(name string) (*unicode.RangeTable, *unicode.RangeTable) {
 // parseUnicodeClass parses a leading Unicode character class like \p{Han}
 // from the beginning of s.  If one is present, it appends the characters to r
 // and returns the new slice r and the remainder of the string.
-func (p *parser) parseUnicodeClass(s string, r []int) (out []int, rest string, err os.Error) {
+func (p *parser) parseUnicodeClass(s string, r []rune) (out []rune, rest string, err os.Error) {
 	if p.flags&UnicodeGroups == 0 || len(s) < 2 || s[0] != '\\' || s[1] != 'p' && s[1] != 'P' {
 		return
 	}
@@ -1533,7 +1533,7 @@ func (p *parser) parseClass(s string) (rest string, err os.Error) {
 
 		// Single character or simple range.
 		rng := t
-		var lo, hi int
+		var lo, hi rune
 		if lo, t, err = p.parseClassChar(t, s); err != nil {
 			return "", err
 		}
@@ -1570,7 +1570,7 @@ func (p *parser) parseClass(s string) (rest string, err os.Error) {
 
 // cleanClass sorts the ranges (pairs of elements of r),
 // merges them, and eliminates duplicates.
-func cleanClass(rp *[]int) []int {
+func cleanClass(rp *[]rune) []rune {
 
 	// Sort by lo increasing, hi decreasing to break ties.
 	sort.Sort(ranges{rp})
@@ -1601,7 +1601,7 @@ func cleanClass(rp *[]int) []int {
 }
 
 // appendLiteral returns the result of appending the literal x to the class r.
-func appendLiteral(r []int, x int, flags Flags) []int {
+func appendLiteral(r []rune, x rune, flags Flags) []rune {
 	if flags&FoldCase != 0 {
 		return appendFoldedRange(r, x, x)
 	}
@@ -1609,7 +1609,7 @@ func appendLiteral(r []int, x int, flags Flags) []int {
 }
 
 // appendRange returns the result of appending the range lo-hi to the class r.
-func appendRange(r []int, lo, hi int) []int {
+func appendRange(r []rune, lo, hi rune) []rune {
 	// Expand last range or next to last range if it overlaps or abuts.
 	// Checking two ranges helps when appending case-folded
 	// alphabets, so that one range can be expanding A-Z and the
@@ -1642,7 +1642,7 @@ const (
 
 // appendFoldedRange returns the result of appending the range lo-hi
 // and its case folding-equivalent runes to the class r.
-func appendFoldedRange(r []int, lo, hi int) []int {
+func appendFoldedRange(r []rune, lo, hi rune) []rune {
 	// Optimizations.
 	if lo <= minFold && hi >= maxFold {
 		// Range is full: folding can't add more.
@@ -1677,7 +1677,7 @@ func appendFoldedRange(r []int, lo, hi int) []int {
 
 // appendClass returns the result of appending the class x to the class r.
 // It assume x is clean.
-func appendClass(r []int, x []int) []int {
+func appendClass(r []rune, x []rune) []rune {
 	for i := 0; i < len(x); i += 2 {
 		r = appendRange(r, x[i], x[i+1])
 	}
@@ -1685,7 +1685,7 @@ func appendClass(r []int, x []int) []int {
 }
 
 // appendFolded returns the result of appending the case folding of the class x to the class r.
-func appendFoldedClass(r []int, x []int) []int {
+func appendFoldedClass(r []rune, x []rune) []rune {
 	for i := 0; i < len(x); i += 2 {
 		r = appendFoldedRange(r, x[i], x[i+1])
 	}
@@ -1694,8 +1694,8 @@ func appendFoldedClass(r []int, x []int) []int {
 
 // appendNegatedClass returns the result of appending the negation of the class x to the class r.
 // It assumes x is clean.
-func appendNegatedClass(r []int, x []int) []int {
-	nextLo := 0
+func appendNegatedClass(r []rune, x []rune) []rune {
+	nextLo := rune('\u0000')
 	for i := 0; i < len(x); i += 2 {
 		lo, hi := x[i], x[i+1]
 		if nextLo <= lo-1 {
@@ -1710,9 +1710,9 @@ func appendNegatedClass(r []int, x []int) []int {
 }
 
 // appendTable returns the result of appending x to the class r.
-func appendTable(r []int, x *unicode.RangeTable) []int {
+func appendTable(r []rune, x *unicode.RangeTable) []rune {
 	for _, xr := range x.R16 {
-		lo, hi, stride := int(xr.Lo), int(xr.Hi), int(xr.Stride)
+		lo, hi, stride := rune(xr.Lo), rune(xr.Hi), rune(xr.Stride)
 		if stride == 1 {
 			r = appendRange(r, lo, hi)
 			continue
@@ -1722,7 +1722,7 @@ func appendTable(r []int, x *unicode.RangeTable) []int {
 		}
 	}
 	for _, xr := range x.R32 {
-		lo, hi, stride := int(xr.Lo), int(xr.Hi), int(xr.Stride)
+		lo, hi, stride := rune(xr.Lo), rune(xr.Hi), rune(xr.Stride)
 		if stride == 1 {
 			r = appendRange(r, lo, hi)
 			continue
@@ -1735,10 +1735,10 @@ func appendTable(r []int, x *unicode.RangeTable) []int {
 }
 
 // appendNegatedTable returns the result of appending the negation of x to the class r.
-func appendNegatedTable(r []int, x *unicode.RangeTable) []int {
-	nextLo := 0 // lo end of next class to add
+func appendNegatedTable(r []rune, x *unicode.RangeTable) []rune {
+	nextLo := rune('\u0000') // lo end of next class to add
 	for _, xr := range x.R16 {
-		lo, hi, stride := int(xr.Lo), int(xr.Hi), int(xr.Stride)
+		lo, hi, stride := rune(xr.Lo), rune(xr.Hi), rune(xr.Stride)
 		if stride == 1 {
 			if nextLo <= lo-1 {
 				r = appendRange(r, nextLo, lo-1)
@@ -1754,7 +1754,7 @@ func appendNegatedTable(r []int, x *unicode.RangeTable) []int {
 		}
 	}
 	for _, xr := range x.R32 {
-		lo, hi, stride := int(xr.Lo), int(xr.Hi), int(xr.Stride)
+		lo, hi, stride := rune(xr.Lo), rune(xr.Hi), rune(xr.Stride)
 		if stride == 1 {
 			if nextLo <= lo-1 {
 				r = appendRange(r, nextLo, lo-1)
@@ -1777,9 +1777,9 @@ func appendNegatedTable(r []int, x *unicode.RangeTable) []int {
 
 // negateClass overwrites r and returns r's negation.
 // It assumes the class r is already clean.
-func negateClass(r []int) []int {
-	nextLo := 0 // lo end of next class to add
-	w := 0      // write index
+func negateClass(r []rune) []rune {
+	nextLo := rune('\u0000') // lo end of next class to add
+	w := 0                   // write index
 	for i := 0; i < len(r); i += 2 {
 		lo, hi := r[i], r[i+1]
 		if nextLo <= lo-1 {
@@ -1801,9 +1801,9 @@ func negateClass(r []int) []int {
 // ranges implements sort.Interface on a []rune.
 // The choice of receiver type definition is strange
 // but avoids an allocation since we already have
-// a *[]int.
+// a *[]rune.
 type ranges struct {
-	p *[]int
+	p *[]rune
 }
 
 func (ra ranges) Less(i, j int) bool {
@@ -1835,7 +1835,7 @@ func checkUTF8(s string) os.Error {
 	return nil
 }
 
-func nextRune(s string) (c int, t string, err os.Error) {
+func nextRune(s string) (c rune, t string, err os.Error) {
 	c, size := utf8.DecodeRuneInString(s)
 	if c == utf8.RuneError && size == 1 {
 		return 0, "", &Error{Code: ErrInvalidUTF8, Expr: s}
@@ -1843,11 +1843,11 @@ func nextRune(s string) (c int, t string, err os.Error) {
 	return c, s[size:], nil
 }
 
-func isalnum(c int) bool {
+func isalnum(c rune) bool {
 	return '0' <= c && c <= '9' || 'A' <= c && c <= 'Z' || 'a' <= c && c <= 'z'
 }
 
-func unhex(c int) int {
+func unhex(c rune) rune {
 	if '0' <= c && c <= '9' {
 		return c - '0'
 	}
diff --git a/src/pkg/regexp/syntax/parse_test.go b/src/pkg/regexp/syntax/parse_test.go
index f20276c59ab..c6e63392c9c 100644
--- a/src/pkg/regexp/syntax/parse_test.go
+++ b/src/pkg/regexp/syntax/parse_test.go
@@ -371,10 +371,10 @@ func dumpRegexp(b *bytes.Buffer, re *Regexp) {
 	b.WriteByte('}')
 }
 
-func mkCharClass(f func(int) bool) string {
+func mkCharClass(f func(rune) bool) string {
 	re := &Regexp{Op: OpCharClass}
-	lo := -1
-	for i := 0; i <= unicode.MaxRune; i++ {
+	lo := rune(-1)
+	for i := rune(0); i <= unicode.MaxRune; i++ {
 		if f(i) {
 			if lo < 0 {
 				lo = i
@@ -392,12 +392,12 @@ func mkCharClass(f func(int) bool) string {
 	return dump(re)
 }
 
-func isUpperFold(rune int) bool {
-	if unicode.IsUpper(rune) {
+func isUpperFold(r rune) bool {
+	if unicode.IsUpper(r) {
 		return true
 	}
-	c := unicode.SimpleFold(rune)
-	for c != rune {
+	c := unicode.SimpleFold(r)
+	for c != r {
 		if unicode.IsUpper(c) {
 			return true
 		}
@@ -407,8 +407,8 @@ func isUpperFold(rune int) bool {
 }
 
 func TestFoldConstants(t *testing.T) {
-	last := -1
-	for i := 0; i <= unicode.MaxRune; i++ {
+	last := rune(-1)
+	for i := rune(0); i <= unicode.MaxRune; i++ {
 		if unicode.SimpleFold(i) == i {
 			continue
 		}
@@ -427,8 +427,8 @@ func TestAppendRangeCollapse(t *testing.T) {
 	// into the earlier ones (it looks back two ranges), so that
 	// the slice never grows very large.
 	// Note that we are not calling cleanClass.
-	var r []int
-	for i := 'A'; i <= 'Z'; i++ {
+	var r []rune
+	for i := rune('A'); i <= 'Z'; i++ {
 		r = appendRange(r, i, i)
 		r = appendRange(r, i+'a'-'A', i+'a'-'A')
 	}
diff --git a/src/pkg/regexp/syntax/perl_groups.go b/src/pkg/regexp/syntax/perl_groups.go
index 05b392c40d8..1a11ca62f0c 100644
--- a/src/pkg/regexp/syntax/perl_groups.go
+++ b/src/pkg/regexp/syntax/perl_groups.go
@@ -3,17 +3,17 @@
 
 package syntax
 
-var code1 = []int{ /* \d */
+var code1 = []rune{ /* \d */
 	0x30, 0x39,
 }
 
-var code2 = []int{ /* \s */
+var code2 = []rune{ /* \s */
 	0x9, 0xa,
 	0xc, 0xd,
 	0x20, 0x20,
 }
 
-var code3 = []int{ /* \w */
+var code3 = []rune{ /* \w */
 	0x30, 0x39,
 	0x41, 0x5a,
 	0x5f, 0x5f,
@@ -28,71 +28,71 @@ var perlGroup = map[string]charGroup{
 	`\w`: {+1, code3},
 	`\W`: {-1, code3},
 }
-var code4 = []int{ /* [:alnum:] */
+var code4 = []rune{ /* [:alnum:] */
 	0x30, 0x39,
 	0x41, 0x5a,
 	0x61, 0x7a,
 }
 
-var code5 = []int{ /* [:alpha:] */
+var code5 = []rune{ /* [:alpha:] */
 	0x41, 0x5a,
 	0x61, 0x7a,
 }
 
-var code6 = []int{ /* [:ascii:] */
+var code6 = []rune{ /* [:ascii:] */
 	0x0, 0x7f,
 }
 
-var code7 = []int{ /* [:blank:] */
+var code7 = []rune{ /* [:blank:] */
 	0x9, 0x9,
 	0x20, 0x20,
 }
 
-var code8 = []int{ /* [:cntrl:] */
+var code8 = []rune{ /* [:cntrl:] */
 	0x0, 0x1f,
 	0x7f, 0x7f,
 }
 
-var code9 = []int{ /* [:digit:] */
+var code9 = []rune{ /* [:digit:] */
 	0x30, 0x39,
 }
 
-var code10 = []int{ /* [:graph:] */
+var code10 = []rune{ /* [:graph:] */
 	0x21, 0x7e,
 }
 
-var code11 = []int{ /* [:lower:] */
+var code11 = []rune{ /* [:lower:] */
 	0x61, 0x7a,
 }
 
-var code12 = []int{ /* [:print:] */
+var code12 = []rune{ /* [:print:] */
 	0x20, 0x7e,
 }
 
-var code13 = []int{ /* [:punct:] */
+var code13 = []rune{ /* [:punct:] */
 	0x21, 0x2f,
 	0x3a, 0x40,
 	0x5b, 0x60,
 	0x7b, 0x7e,
 }
 
-var code14 = []int{ /* [:space:] */
+var code14 = []rune{ /* [:space:] */
 	0x9, 0xd,
 	0x20, 0x20,
 }
 
-var code15 = []int{ /* [:upper:] */
+var code15 = []rune{ /* [:upper:] */
 	0x41, 0x5a,
 }
 
-var code16 = []int{ /* [:word:] */
+var code16 = []rune{ /* [:word:] */
 	0x30, 0x39,
 	0x41, 0x5a,
 	0x5f, 0x5f,
 	0x61, 0x7a,
 }
 
-var code17 = []int{ /* [:xdigit:] */
+var code17 = []rune{ /* [:xdigit:] */
 	0x30, 0x39,
 	0x41, 0x46,
 	0x61, 0x66,
diff --git a/src/pkg/regexp/syntax/prog.go b/src/pkg/regexp/syntax/prog.go
index ced45da077b..f5b697a59ae 100644
--- a/src/pkg/regexp/syntax/prog.go
+++ b/src/pkg/regexp/syntax/prog.go
@@ -51,7 +51,7 @@ const (
 // at the beginning of the text.
 // Passing r2 == -1 indicates that the position is
 // at the end of the text.
-func EmptyOpContext(r1, r2 int) EmptyOp {
+func EmptyOpContext(r1, r2 rune) EmptyOp {
 	var op EmptyOp
 	if r1 < 0 {
 		op |= EmptyBeginText | EmptyBeginLine
@@ -76,7 +76,7 @@ func EmptyOpContext(r1, r2 int) EmptyOp {
 // IsWordChar reports whether r is consider a ``word character''
 // during the evaluation of the \b and \B zero-width assertions.
 // These assertions are ASCII-only: the word characters are [A-Za-z0-9_].
-func IsWordChar(r int) bool {
+func IsWordChar(r rune) bool {
 	return 'A' <= r && r <= 'Z' || 'a' <= r && r <= 'z' || '0' <= r && r <= '9' || r == '_'
 }
 
@@ -85,7 +85,7 @@ type Inst struct {
 	Op   InstOp
 	Out  uint32 // all but InstMatch, InstFail
 	Arg  uint32 // InstAlt, InstAltMatch, InstCapture, InstEmptyWidth
-	Rune []int
+	Rune []rune
 }
 
 func (p *Prog) String() string {
@@ -161,7 +161,7 @@ Loop:
 
 // MatchRune returns true if the instruction matches (and consumes) r.
 // It should only be called when i.Op == InstRune.
-func (i *Inst) MatchRune(r int) bool {
+func (i *Inst) MatchRune(r rune) bool {
 	rune := i.Rune
 
 	// Special case: single-rune slice is from literal string, not char class.
@@ -210,17 +210,17 @@ func (i *Inst) MatchRune(r int) bool {
 
 // As per re2's Prog::IsWordChar. Determines whether rune is an ASCII word char.
 // Since we act on runes, it would be easy to support Unicode here.
-func wordRune(rune int) bool {
-	return rune == '_' ||
-		('A' <= rune && rune <= 'Z') ||
-		('a' <= rune && rune <= 'z') ||
-		('0' <= rune && rune <= '9')
+func wordRune(r rune) bool {
+	return r == '_' ||
+		('A' <= r && r <= 'Z') ||
+		('a' <= r && r <= 'z') ||
+		('0' <= r && r <= '9')
 }
 
 // MatchEmptyWidth returns true if the instruction matches
 // an empty string between the runes before and after.
 // It should only be called when i.Op == InstEmptyWidth.
-func (i *Inst) MatchEmptyWidth(before int, after int) bool {
+func (i *Inst) MatchEmptyWidth(before rune, after rune) bool {
 	switch EmptyOp(i.Arg) {
 	case EmptyBeginLine:
 		return before == '\n' || before == -1
diff --git a/src/pkg/regexp/syntax/regexp.go b/src/pkg/regexp/syntax/regexp.go
index 033848df28a..b5ddab1d16b 100644
--- a/src/pkg/regexp/syntax/regexp.go
+++ b/src/pkg/regexp/syntax/regexp.go
@@ -22,8 +22,8 @@ type Regexp struct {
 	Flags    Flags
 	Sub      []*Regexp  // subexpressions, if any
 	Sub0     [1]*Regexp // storage for short Sub
-	Rune     []int      // matched runes, for OpLiteral, OpCharClass
-	Rune0    [2]int     // storage for short Rune
+	Rune     []rune     // matched runes, for OpLiteral, OpCharClass
+	Rune0    [2]rune    // storage for short Rune
 	Min, Max int        // min, max for OpRepeat
 	Cap      int        // capturing index, for OpCapture
 	Name     string     // capturing name, for OpCapture
@@ -252,7 +252,7 @@ func (re *Regexp) String() string {
 
 const meta = `\.+*?()|[]{}^$`
 
-func escape(b *bytes.Buffer, r int, force bool) {
+func escape(b *bytes.Buffer, r rune, force bool) {
 	if unicode.IsPrint(r) {
 		if strings.IndexRune(meta, r) >= 0 || force {
 			b.WriteRune('\\')
@@ -277,7 +277,7 @@ func escape(b *bytes.Buffer, r int, force bool) {
 	default:
 		if r < 0x100 {
 			b.WriteString(`\x`)
-			s := strconv.Itob(r, 16)
+			s := strconv.Itob(int(r), 16)
 			if len(s) == 1 {
 				b.WriteRune('0')
 			}
@@ -285,7 +285,7 @@ func escape(b *bytes.Buffer, r int, force bool) {
 			break
 		}
 		b.WriteString(`\x{`)
-		b.WriteString(strconv.Itob(r, 16))
+		b.WriteString(strconv.Itob(int(r), 16))
 		b.WriteString(`}`)
 	}
 }