diff --git a/src/backend/parser/parse_type.c b/src/backend/parser/parse_type.c
index be75dc6ab0..63b4e96962 100644
--- a/src/backend/parser/parse_type.c
+++ b/src/backend/parser/parse_type.c
@@ -742,7 +742,7 @@ typeStringToTypeName(const char *str, Node *escontext)
 	ErrorContextCallback ptserrcontext;
 
 	/* make sure we give useful error for empty input */
-	if (strspn(str, " \t\n\r\f") == strlen(str))
+	if (strspn(str, " \t\n\r\f\v") == strlen(str))
 		goto fail;
 
 	/*
diff --git a/src/backend/parser/scan.l b/src/backend/parser/scan.l
index b2216a9eac..a6c67c7151 100644
--- a/src/backend/parser/scan.l
+++ b/src/backend/parser/scan.l
@@ -219,7 +219,7 @@ extern void core_yyset_column(int column_no, yyscan_t yyscanner);
  * to agree.
  */
 
-space			[ \t\n\r\f]
+space			[ \t\n\r\f\v]
 horiz_space		[ \t\f]
 newline			[\n\r]
 non_newline		[^\n\r]
@@ -1414,6 +1414,8 @@ unescape_single_char(unsigned char c, core_yyscan_t yyscanner)
 			return '\r';
 		case 't':
 			return '\t';
+		case 'v':
+			return '\v';
 		default:
 			/* check for backslash followed by non-7-bit-ASCII */
 			if (c == '\0' || IS_HIGHBIT_SET(c))
diff --git a/src/backend/parser/scansup.c b/src/backend/parser/scansup.c
index ed67f5f5fe..4f0005a114 100644
--- a/src/backend/parser/scansup.c
+++ b/src/backend/parser/scansup.c
@@ -121,6 +121,7 @@ scanner_isspace(char ch)
 		ch == '\t' ||
 		ch == '\n' ||
 		ch == '\r' ||
+		ch == '\v' ||
 		ch == '\f')
 		return true;
 	return false;
diff --git a/src/backend/replication/repl_scanner.l b/src/backend/replication/repl_scanner.l
index cb467ca46f..1cc7fb858c 100644
--- a/src/backend/replication/repl_scanner.l
+++ b/src/backend/replication/repl_scanner.l
@@ -73,7 +73,7 @@ static void addlitchar(unsigned char ychar);
 %x xd
 %x xq
 
-space			[ \t\n\r\f]
+space			[ \t\n\r\f\v]
 
 quote			'
 quotestop		{quote}
diff --git a/src/backend/utils/adt/arrayfuncs.c b/src/backend/utils/adt/arrayfuncs.c
index 9000f83a83..4359dbd83d 100644
--- a/src/backend/utils/adt/arrayfuncs.c
+++ b/src/backend/utils/adt/arrayfuncs.c
@@ -24,6 +24,7 @@
 #include "nodes/nodeFuncs.h"
 #include "nodes/supportnodes.h"
 #include "optimizer/optimizer.h"
+#include "parser/scansup.h"
 #include "port/pg_bitutils.h"
 #include "utils/array.h"
 #include "utils/arrayaccess.h"
@@ -89,7 +90,6 @@ typedef struct ArrayIteratorData
 	int			current_item;	/* the item # we're at in the array */
 }			ArrayIteratorData;
 
-static bool array_isspace(char ch);
 static int	ArrayCount(const char *str, int *dim, char typdelim,
 					   Node *escontext);
 static bool ReadArrayStr(char *arrayStr, const char *origStr,
@@ -254,7 +254,7 @@ array_in(PG_FUNCTION_ARGS)
 		 * Note: we currently allow whitespace between, but not within,
 		 * dimension items.
 		 */
-		while (array_isspace(*p))
+		while (scanner_isspace(*p))
 			p++;
 		if (*p != '[')
 			break;				/* no more dimension items */
@@ -338,7 +338,7 @@ array_in(PG_FUNCTION_ARGS)
 					 errdetail("Missing \"%s\" after array dimensions.",
 							   ASSGN)));
 		p += strlen(ASSGN);
-		while (array_isspace(*p))
+		while (scanner_isspace(*p))
 			p++;
 
 		/*
@@ -434,27 +434,6 @@ array_in(PG_FUNCTION_ARGS)
 	PG_RETURN_ARRAYTYPE_P(retval);
 }
 
-/*
- * array_isspace() --- a non-locale-dependent isspace()
- *
- * We used to use isspace() for parsing array values, but that has
- * undesirable results: an array value might be silently interpreted
- * differently depending on the locale setting.  Now we just hard-wire
- * the traditional ASCII definition of isspace().
- */
-static bool
-array_isspace(char ch)
-{
-	if (ch == ' ' ||
-		ch == '\t' ||
-		ch == '\n' ||
-		ch == '\r' ||
-		ch == '\v' ||
-		ch == '\f')
-		return true;
-	return false;
-}
-
 /*
  * ArrayCount
  *	 Determines the dimensions for an array string.
@@ -654,7 +633,7 @@ ArrayCount(const char *str, int *dim, char typdelim, Node *escontext)
 							itemdone = true;
 							nelems[nest_level - 1]++;
 						}
-						else if (!array_isspace(*ptr))
+						else if (!scanner_isspace(*ptr))
 						{
 							/*
 							 * Other non-space characters must be after a
@@ -684,7 +663,7 @@ ArrayCount(const char *str, int *dim, char typdelim, Node *escontext)
 	/* only whitespace is allowed after the closing brace */
 	while (*ptr)
 	{
-		if (!array_isspace(*ptr++))
+		if (!scanner_isspace(*ptr++))
 			ereturn(escontext, -1,
 					(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
 					 errmsg("malformed array literal: \"%s\"", str),
@@ -884,7 +863,7 @@ ReadArrayStr(char *arrayStr,
 						indx[ndim - 1]++;
 						srcptr++;
 					}
-					else if (array_isspace(*srcptr))
+					else if (scanner_isspace(*srcptr))
 					{
 						/*
 						 * If leading space, drop it immediately.  Else, copy
@@ -1176,7 +1155,7 @@ array_out(PG_FUNCTION_ARGS)
 					overall_length += 1;
 				}
 				else if (ch == '{' || ch == '}' || ch == typdelim ||
-						 array_isspace(ch))
+						 scanner_isspace(ch))
 					needquote = true;
 			}
 		}
diff --git a/src/fe_utils/psqlscan.l b/src/fe_utils/psqlscan.l
index 84754aca4a..84585d78b4 100644
--- a/src/fe_utils/psqlscan.l
+++ b/src/fe_utils/psqlscan.l
@@ -155,7 +155,7 @@ extern void psql_yyset_column(int column_no, yyscan_t yyscanner);
  * to agree.
  */
 
-space			[ \t\n\r\f]
+space			[ \t\n\r\f\v]
 horiz_space		[ \t\f]
 newline			[\n\r]
 non_newline		[^\n\r]
diff --git a/src/fe_utils/string_utils.c b/src/fe_utils/string_utils.c
index 0429a72bfe..58b21c4d6a 100644
--- a/src/fe_utils/string_utils.c
+++ b/src/fe_utils/string_utils.c
@@ -761,7 +761,7 @@ appendPGArray(PQExpBuffer buffer, const char *value)
 
 			if (ch == '"' || ch == '\\' ||
 				ch == '{' || ch == '}' || ch == ',' ||
-			/* these match array_isspace(): */
+			/* these match scanner_isspace(): */
 				ch == ' ' || ch == '\t' || ch == '\n' ||
 				ch == '\r' || ch == '\v' || ch == '\f')
 			{
diff --git a/src/bin/psql/psqlscanslash.l b/src/bin/psql/psqlscanslash.l
index 5c020f30b9..1461fa3d3e 100644
--- a/src/bin/psql/psqlscanslash.l
+++ b/src/bin/psql/psqlscanslash.l
@@ -108,7 +108,7 @@ extern void slash_yyset_column(int column_no, yyscan_t yyscanner);
 /*
  * Assorted character class definitions that should match psqlscan.l.
  */
-space			[ \t\n\r\f]
+space			[ \t\n\r\f\v]
 quote			'
 xeoctesc		[\\][0-7]{1,3}
 xehexesc		[\\]x[0-9A-Fa-f]{1,2}
diff --git a/contrib/cube/cubescan.l b/contrib/cube/cubescan.l
index 49cb699216..a30fbfc311 100644
--- a/contrib/cube/cubescan.l
+++ b/contrib/cube/cubescan.l
@@ -63,7 +63,7 @@ NaN          [nN][aA][nN]
 \(           cube_yylval = "("; return O_PAREN;
 \)           cube_yylval = ")"; return C_PAREN;
 \,           cube_yylval = ","; return COMMA;
-[ \t\n\r\f]+ /* discard spaces */
+[ \t\n\r\f\v]+ /* discard spaces */
 .            return yytext[0]; /* alert parser of the garbage */
 
 %%
diff --git a/contrib/hstore/expected/hstore_utf8.out b/contrib/hstore/expected/hstore_utf8.out
index 4405824413..bbc885a181 100644
--- a/contrib/hstore/expected/hstore_utf8.out
+++ b/contrib/hstore/expected/hstore_utf8.out
@@ -34,3 +34,34 @@ SELECT 'keyąfoo=>valueą'::hstore;
  "keyąfoo"=>"valueą"
 (1 row)
 
+-- More patterns that may depend on isspace() and locales, all discarded.
+SELECT E'key\u000A=>value\u000A'::hstore; -- \n
+     hstore     
+----------------
+ "key"=>"value"
+(1 row)
+
+SELECT E'key\u0009=>value\u0009'::hstore; -- \t
+     hstore     
+----------------
+ "key"=>"value"
+(1 row)
+
+SELECT E'key\u000D=>value\u000D'::hstore; -- \r
+     hstore     
+----------------
+ "key"=>"value"
+(1 row)
+
+SELECT E'key\u000B=>value\u000B'::hstore; -- \v
+     hstore     
+----------------
+ "key"=>"value"
+(1 row)
+
+SELECT E'key\u000C=>value\u000C'::hstore; -- \f
+     hstore     
+----------------
+ "key"=>"value"
+(1 row)
+
diff --git a/contrib/hstore/sql/hstore_utf8.sql b/contrib/hstore/sql/hstore_utf8.sql
index face878324..38c9481ee6 100644
--- a/contrib/hstore/sql/hstore_utf8.sql
+++ b/contrib/hstore/sql/hstore_utf8.sql
@@ -17,3 +17,10 @@ SELECT E'key\u0105=>value\u0105'::hstore;
 SELECT 'keyą=>valueą'::hstore;
 SELECT 'ą=>ą'::hstore;
 SELECT 'keyąfoo=>valueą'::hstore;
+
+-- More patterns that may depend on isspace() and locales, all discarded.
+SELECT E'key\u000A=>value\u000A'::hstore; -- \n
+SELECT E'key\u0009=>value\u0009'::hstore; -- \t
+SELECT E'key\u000D=>value\u000D'::hstore; -- \r
+SELECT E'key\u000B=>value\u000B'::hstore; -- \v
+SELECT E'key\u000C=>value\u000C'::hstore; -- \f
diff --git a/contrib/seg/segscan.l b/contrib/seg/segscan.l
index a1e9e9937e..4ad529eccc 100644
--- a/contrib/seg/segscan.l
+++ b/contrib/seg/segscan.l
@@ -59,7 +59,7 @@ float        ({integer}|{real})([eE]{integer})?
 \<           seg_yylval.text = "<"; return EXTENSION;
 \>           seg_yylval.text = ">"; return EXTENSION;
 \~           seg_yylval.text = "~"; return EXTENSION;
-[ \t\n\r\f]+ /* discard spaces */
+[ \t\n\r\f\v]+ /* discard spaces */
 .            return yytext[0]; /* alert parser of the garbage */
 
 %%
diff --git a/src/interfaces/ecpg/preproc/pgc.l b/src/interfaces/ecpg/preproc/pgc.l
index dcd567e8c3..8defe73f0e 100644
--- a/src/interfaces/ecpg/preproc/pgc.l
+++ b/src/interfaces/ecpg/preproc/pgc.l
@@ -186,7 +186,7 @@ static struct _if_value
  * to agree.
  */
 
-space			[ \t\n\r\f]
+space			[ \t\n\r\f\v]
 horiz_space		[ \t\f]
 newline			[\n\r]
 non_newline		[^\n\r]
@@ -1721,7 +1721,8 @@ ecpg_isspace(char ch)
 		ch == '\t' ||
 		ch == '\n' ||
 		ch == '\r' ||
-		ch == '\f')
+		ch == '\f' ||
+		ch == '\v')
 		return true;
 	return false;
 }