diff --git a/src/backend/regex/engine.c b/src/backend/regex/engine.c
index 96be85671a..3c323586d6 100644
--- a/src/backend/regex/engine.c
+++ b/src/backend/regex/engine.c
@@ -90,12 +90,23 @@ extern "C" {
 #endif
 
 /* === engine.c === */
-static int matcher __P((struct re_guts *g, char *string, size_t nmatch, regmatch_t pmatch[], int eflags));
-static char *dissect __P((struct match *m, char *start, char *stop, sopno startst, sopno stopst));
-static char *backref __P((struct match *m, char *start, char *stop, sopno startst, sopno stopst, sopno lev));
-static char *fast __P((struct match *m, char *start, char *stop, sopno startst, sopno stopst));
-static char *slow __P((struct match *m, char *start, char *stop, sopno startst, sopno stopst));
-static states step __P((struct re_guts *g, sopno start, sopno stop, states bef, int ch, states aft));
+static int 
+matcher(struct re_guts *g, char *string, size_t nmatch, 
+         regmatch_t pmatch[], int eflags);
+static char *
+dissect(struct match *m, char *start, char *stop, 
+        sopno startst, sopno stopst);
+static char *
+backref(struct match *m, char *start, char *stop, 
+        sopno startst, sopno stopst, sopno lev);
+static char *
+fast(struct match *m, char *start, char *stop, 
+     sopno startst, sopno stopst);
+static char *
+slow(struct match *m, char *start, char *stop, sopno startst, sopno stopst);
+static states 
+step(struct re_guts *g, sopno start, 
+     sopno stop, states bef, int ch, states aft);
 #define	BOL	(OUT+1)
 #define	EOL	(BOL+1)
 #define	BOLEOL	(BOL+2)
@@ -106,13 +117,17 @@ static states step __P((struct re_guts *g, sopno start, sopno stop, states bef,
 #define	NONCHAR(c)	((c) > CHAR_MAX)
 #define	NNONCHAR	(CODEMAX-CHAR_MAX)
 #ifdef REDEBUG
-static void print __P((struct match *m, char *caption, states st, int ch, FILE *d));
+static void 
+print(struct match *m, char *caption, states st, int ch, FILE *d);
 #endif
 #ifdef REDEBUG
-static void at __P((struct match *m, char *title, char *start, char *stop, sopno startst, sopno stopst));
+static void 
+at(struct match *m, char *title, char *start, char *stop, 
+   sopno startst, sopno stopst);
 #endif
 #ifdef REDEBUG
-static char *pchar __P((int ch));
+static char *
+pchar(int ch);
 #endif
 
 #ifdef __cplusplus
diff --git a/src/backend/regex/regcomp.c b/src/backend/regex/regcomp.c
index d59e71d101..aca663aac5 100644
--- a/src/backend/regex/regcomp.c
+++ b/src/backend/regex/regcomp.c
@@ -79,46 +79,43 @@ extern "C" {
 #endif
 
 /* === regcomp.c === */
-static void p_ere __P((struct parse *p, int stop));
-static void p_ere_exp __P((struct parse *p));
-static void p_str __P((struct parse *p));
-static void p_bre __P((struct parse *p, int end1, int end2));
-static int p_simp_re __P((struct parse *p, int starordinary));
-static int p_count __P((struct parse *p));
-static void p_bracket __P((struct parse *p));
-static void p_b_term __P((struct parse *p, cset *cs));
-static void p_b_cclass __P((struct parse *p, cset *cs));
-static void p_b_eclass __P((struct parse *p, cset *cs));
-static char p_b_symbol __P((struct parse *p));
-static char p_b_coll_elem __P((struct parse *p, int endc));
-static char othercase __P((int ch));
-static void bothcases __P((struct parse *p, int ch));
-static void ordinary __P((struct parse *p, int ch));
-static void nonnewline __P((struct parse *p));
-static void repeat __P((struct parse *p, sopno start, int from, int to));
-static int seterr __P((struct parse *p, int e));
-static cset *allocset __P((struct parse *p));
-static void freeset __P((struct parse *p, cset *cs));
-static int freezeset __P((struct parse *p, cset *cs));
-static int firstch __P((struct parse *p, cset *cs));
-static int nch __P((struct parse *p, cset *cs));
-static void mcadd __P((struct parse *p, cset *cs, char *cp));
-/* static void mcsub __P((cset *cs, char *cp)); */
-/*static int mcin __P((cset *cs, char *cp));*/
-/*static char *mcfind __P((cset *cs, char *cp)); */
-static void mcinvert __P((struct parse *p, cset *cs));
-static void mccase __P((struct parse *p, cset *cs));
-static int isinsets __P((struct re_guts *g, int c));
-static int samesets __P((struct re_guts *g, int c1, int c2));
-static void categorize __P((struct parse *p, struct re_guts *g));
-static sopno dupl __P((struct parse *p, sopno start, sopno finish));
-static void doemit __P((struct parse *p, sop op, size_t opnd));
-static void doinsert __P((struct parse *p, sop op, size_t opnd, sopno pos));
-static void dofwd __P((struct parse *p, sopno pos, sop value));
-static void enlarge __P((struct parse *p, sopno size));
-static void stripsnug __P((struct parse *p, struct re_guts *g));
-static void findmust __P((struct parse *p, struct re_guts *g));
-static sopno pluscount __P((struct parse *p, struct re_guts *g));
+static void p_ere(struct parse *p, int stop);
+static void p_ere_exp(struct parse *p);
+static void p_str(struct parse *p);
+static void p_bre(struct parse *p, int end1, int end2);
+static int p_simp_re(struct parse *p, int starordinary);
+static int p_count(struct parse *p);
+static void p_bracket(struct parse *p);
+static void p_b_term(struct parse *p, cset *cs);
+static void p_b_cclass(struct parse *p, cset *cs);
+static void p_b_eclass(struct parse *p, cset *cs);
+static char p_b_symbol(struct parse *p);
+static char p_b_coll_elem(struct parse *p, int endc);
+static char othercase(int ch);
+static void bothcases(struct parse *p, int ch);
+static void ordinary(struct parse *p, int ch);
+static void nonnewline(struct parse *p);
+static void repeat(struct parse *p, sopno start, int from, int to);
+static int seterr(struct parse *p, int e);
+static cset *allocset(struct parse *p);
+static void freeset(struct parse *p, cset *cs);
+static int freezeset(struct parse *p, cset *cs);
+static int firstch(struct parse *p, cset *cs);
+static int nch(struct parse *p, cset *cs);
+static void mcadd(struct parse *p, cset *cs, char *cp);
+static void mcinvert(struct parse *p, cset *cs);
+static void mccase(struct parse *p, cset *cs);
+static int isinsets(struct re_guts *g, int c);
+static int samesets(struct re_guts *g, int c1, int c2);
+static void categorize(struct parse *p, struct re_guts *g);
+static sopno dupl(struct parse *p, sopno start, sopno finish);
+static void doemit(struct parse *p, sop op, size_t opnd);
+static void doinsert(struct parse *p, sop op, size_t opnd, sopno pos);
+static void dofwd(struct parse *p, sopno pos, sop value);
+static void enlarge(struct parse *p, sopno size);
+static void stripsnug(struct parse *p, struct re_guts *g);
+static void findmust(struct parse *p, struct re_guts *g);
+static sopno pluscount(struct parse *p, struct re_guts *g);
 
 #ifdef __cplusplus
 }
diff --git a/src/backend/regex/regerror.c b/src/backend/regex/regerror.c
index fef668fadf..536f70ceb8 100644
--- a/src/backend/regex/regerror.c
+++ b/src/backend/regex/regerror.c
@@ -58,7 +58,7 @@ extern "C" {
 #endif
 
 /* === regerror.c === */
-static char *regatoi __P((const regex_t *preg, char *localbuf));
+static char *regatoi(const regex_t *preg, char *localbuf);
 
 #ifdef __cplusplus
 }