diff --git a/src/backend/commands/dbcommands.c b/src/backend/commands/dbcommands.c
index e0753c1badcc299e2bac45f3bdd2f23f59d70cbc..2589a2523e07c9543c99c7d7b446438d62382b89 100644
--- a/src/backend/commands/dbcommands.c
+++ b/src/backend/commands/dbcommands.c
@@ -1030,6 +1030,11 @@ createdb(ParseState *pstate, const CreatedbStmt *stmt)
 
 	if (dblocprovider == COLLPROVIDER_ICU)
 	{
+#ifndef USE_ICU
+		ereport(ERROR,
+				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+				 errmsg("ICU is not supported in this build")));
+#else
 		if (!(is_encoding_supported_by_icu(encoding)))
 			ereport(ERROR,
 					(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
@@ -1046,6 +1051,7 @@ createdb(ParseState *pstate, const CreatedbStmt *stmt)
 					 errmsg("ICU locale must be specified")));
 
 		check_icu_locale(dbiculocale);
+#endif
 	}
 	else
 	{
diff --git a/src/backend/utils/adt/pg_locale.c b/src/backend/utils/adt/pg_locale.c
index 2b42d9ccd8b751bcb5cda3a1f4c7803a68bc0a4a..743f11e1d1fd62d500fc2846976472d13e08046b 100644
--- a/src/backend/utils/adt/pg_locale.c
+++ b/src/backend/utils/adt/pg_locale.c
@@ -1945,15 +1945,12 @@ icu_set_collation_attributes(UCollator *collator, const char *loc)
 	}
 }
 
-#endif							/* USE_ICU */
-
 /*
  * Check if the given locale ID is valid, and ereport(ERROR) if it isn't.
  */
 void
 check_icu_locale(const char *icu_locale)
 {
-#ifdef USE_ICU
 	UCollator  *collator;
 	UErrorCode	status;
 
@@ -1967,13 +1964,10 @@ check_icu_locale(const char *icu_locale)
 	if (U_ICU_VERSION_MAJOR_NUM < 54)
 		icu_set_collation_attributes(collator, icu_locale);
 	ucol_close(collator);
-#else
-	ereport(ERROR,
-			(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
-			 errmsg("ICU is not supported in this build")));
-#endif
 }
 
+#endif							/* USE_ICU */
+
 /*
  * These functions convert from/to libc's wchar_t, *not* pg_wchar_t.
  * Therefore we keep them here rather than with the mbutils code.
diff --git a/src/bin/initdb/initdb.c b/src/bin/initdb/initdb.c
index f61a04305590c7d09ec59fe202d6f22c0a605827..82e6644f89b07004c067785c86cad83e10b1282c 100644
--- a/src/bin/initdb/initdb.c
+++ b/src/bin/initdb/initdb.c
@@ -2047,9 +2047,12 @@ check_locale_encoding(const char *locale, int user_enc)
  *
  * this should match the similar check in the backend createdb() function
  */
-static bool
+static void
 check_icu_locale_encoding(int user_enc)
 {
+#ifndef USE_ICU
+	pg_fatal("ICU is not supported in this build");
+#else
 	if (!(is_encoding_supported_by_icu(user_enc)))
 	{
 		pg_log_error("encoding mismatch");
@@ -2058,9 +2061,17 @@ check_icu_locale_encoding(int user_enc)
 		pg_log_error_hint("Rerun %s and either do not specify an encoding explicitly, "
 						  "or choose a matching combination.",
 						  progname);
-		return false;
+		exit(1);
 	}
-	return true;
+
+	if (!icu_locale)
+		pg_fatal("ICU locale must be specified");
+
+	/*
+	 * In supported builds, the ICU locale ID will be checked by the backend
+	 * during post-bootstrap initialization.
+	 */
+#endif
 }
 
 /*
@@ -2113,20 +2124,6 @@ setlocales(void)
 	check_locale_name(LC_CTYPE, lc_messages, &canonname);
 	lc_messages = canonname;
 #endif
-
-	if (locale_provider == COLLPROVIDER_ICU)
-	{
-		if (!icu_locale)
-			pg_fatal("ICU locale must be specified");
-
-		/*
-		 * In supported builds, the ICU locale ID will be checked by the
-		 * backend during post-bootstrap initialization.
-		 */
-#ifndef USE_ICU
-		pg_fatal("ICU is not supported in this build");
-#endif
-	}
 }
 
 /*
@@ -2388,9 +2385,8 @@ setup_locale_encoding(void)
 		!check_locale_encoding(lc_collate, encodingid))
 		exit(1);				/* check_locale_encoding printed the error */
 
-	if (locale_provider == COLLPROVIDER_ICU &&
-		!check_icu_locale_encoding(encodingid))
-		exit(1);
+	if (locale_provider == COLLPROVIDER_ICU)
+		check_icu_locale_encoding(encodingid);
 }
 
 
diff --git a/src/bin/initdb/t/001_initdb.pl b/src/bin/initdb/t/001_initdb.pl
index 164fc11cbffc8c466f84d51c07106b602d022bc6..884506a1bc58752669694df95c6dcb05726507a5 100644
--- a/src/bin/initdb/t/001_initdb.pl
+++ b/src/bin/initdb/t/001_initdb.pl
@@ -123,28 +123,41 @@ if ($ENV{with_icu} eq 'yes')
 		[
 			'initdb',                '--no-sync',
 			'--locale-provider=icu', '--encoding=SQL_ASCII',
-			'--icu-locale=en', "$tempdir/dataX"
+			"$tempdir/dataX"
 		],
 		qr/error: encoding mismatch/,
 		'fails for encoding not supported by ICU');
 }
 else
 {
-	command_fails(
+	command_fails_like(
 		[ 'initdb', '--no-sync', '--locale-provider=icu', "$tempdir/data2" ],
+		qr/error: ICU is not supported in this build/,
 		'locale provider ICU fails since no ICU support');
+
+	command_fails_like(
+		[
+			'initdb',                '--no-sync',
+			'--locale-provider=icu', '--encoding=SQL_ASCII',
+			"$tempdir/data2"
+		],
+		qr/error: ICU is not supported in this build/,
+		'locale provider ICU with not supported ICU encoding fails since no ICU support'
+	);
 }
 
-command_fails(
+command_fails_like(
 	[ 'initdb', '--no-sync', '--locale-provider=xyz', "$tempdir/dataX" ],
+	qr/error: unrecognized locale provider: xyz/,
 	'fails for invalid locale provider');
 
-command_fails(
+command_fails_like(
 	[
 		'initdb',                 '--no-sync',
 		'--locale-provider=libc', '--icu-locale=en',
 		"$tempdir/dataX"
 	],
+	qr/error: --icu-locale cannot be specified unless locale provider "icu" is chosen/,
 	'fails for invalid option combination');
 
 done_testing();
diff --git a/src/bin/scripts/t/020_createdb.pl b/src/bin/scripts/t/020_createdb.pl
index 8ed8628db11c1410db4987f11250535bfb1aa008..7a262d227061ace1f72498371ab0c4fa8767d7a9 100644
--- a/src/bin/scripts/t/020_createdb.pl
+++ b/src/bin/scripts/t/020_createdb.pl
@@ -30,11 +30,12 @@ if ($ENV{with_icu} eq 'yes')
 	# This fails because template0 uses libc provider and has no ICU
 	# locale set.  It would succeed if template0 used the icu
 	# provider.  XXX Maybe split into multiple tests?
-	$node->command_fails(
+	$node->command_fails_like(
 		[
 			'createdb', '-T', 'template0', '-E', 'UTF8',
 			'--locale-provider=icu', 'foobar4'
 		],
+		qr/ERROR:  ICU locale must be specified/,
 		'create database with ICU fails without ICU locale specified');
 
 	$node->issues_sql_like(
@@ -46,12 +47,13 @@ if ($ENV{with_icu} eq 'yes')
 		qr/statement: CREATE DATABASE foobar5 .* LOCALE_PROVIDER icu ICU_LOCALE 'en'/,
 		'create database with ICU locale specified');
 
-	$node->command_fails(
+	$node->command_fails_like(
 		[
 			'createdb', '-T', 'template0', '-E', 'UTF8',
 			'--locale-provider=icu',
 			'--icu-locale=@colNumeric=lower', 'foobarX'
 		],
+		qr/ERROR:  could not open collator for locale/,
 		'fails for invalid ICU locale');
 
 	$node->command_fails_like(
@@ -78,18 +80,39 @@ if ($ENV{with_icu} eq 'yes')
 }
 else
 {
-	$node->command_fails(
+	$node->command_fails_like(
 		[ 'createdb', '-T', 'template0', '--locale-provider=icu', 'foobar4' ],
+		qr/ERROR:  ICU is not supported in this build/,
 		'create database with ICU fails since no ICU support');
+
+	$node->command_fails_like(
+		[
+			'createdb',             '-T',
+			'template0',            '--locale-provider=icu',
+			'--encoding=SQL_ASCII', 'foobar4'
+		],
+		qr/ERROR:  ICU is not supported in this build/,
+		'create database with ICU and not supported ICU encoding fails since no ICU support'
+	);
 }
 
 $node->command_fails([ 'createdb', 'foobar1' ],
 	'fails if database already exists');
 
-$node->command_fails(
+$node->command_fails_like(
 	[ 'createdb', '-T', 'template0', '--locale-provider=xyz', 'foobarX' ],
+	qr/ERROR:  unrecognized locale provider: xyz/,
 	'fails for invalid locale provider');
 
+$node->command_fails_like(
+	[
+		'createdb',        '-T',
+		'template0',       '--locale-provider=libc',
+		'--icu-locale=en', 'foobarX'
+	],
+	qr/ERROR:  ICU locale cannot be specified unless locale provider is ICU/,
+	'fails for invalid option combination');
+
 # Check use of templates with shared dependencies copied from the template.
 my ($ret, $stdout, $stderr) = $node->psql(
 	'foobar2',
diff --git a/src/include/utils/pg_locale.h b/src/include/utils/pg_locale.h
index a87594212364aaac3337ef07188dd291d62299d7..6e8af399769fdb257a65446b3c476bbfeca49f33 100644
--- a/src/include/utils/pg_locale.h
+++ b/src/include/utils/pg_locale.h
@@ -104,8 +104,8 @@ extern char *get_collation_actual_version(char collprovider, const char *collcol
 #ifdef USE_ICU
 extern int32_t icu_to_uchar(UChar **buff_uchar, const char *buff, size_t nbytes);
 extern int32_t icu_from_uchar(char **result, const UChar *buff_uchar, int32_t len_uchar);
-#endif
 extern void check_icu_locale(const char *icu_locale);
+#endif
 
 /* These functions convert from/to libc's wchar_t, *not* pg_wchar_t */
 extern size_t wchar2char(char *to, const wchar_t *from, size_t tolen,