From 51c86d422942152c960d02c7478483d3b21f1390 Mon Sep 17 00:00:00 2001
From: Jeff Davis <jeff@j-davis.com>
Date: Wed, 9 Oct 2024 22:28:15 -0700
Subject: [PATCH v18] Fix missed case for builtin collation provider.

A missed check for the builtin collation provider could result in
falling through to call isalpha().

This does not appear to have practical consequences because it only
happens for characters in the ASCII range. Regardless, the builtin
provider should not be calling libc functions, so backpatch.

Backpatch-through: 17
---
 src/backend/utils/adt/like_support.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/src/backend/utils/adt/like_support.c b/src/backend/utils/adt/like_support.c
index 79c4ddc757..8b15509a3b 100644
--- a/src/backend/utils/adt/like_support.c
+++ b/src/backend/utils/adt/like_support.c
@@ -1500,13 +1500,11 @@ pattern_char_isalpha(char c, bool is_multibyte,
 		return (c >= 'A' && c <= 'Z') || (c >= 'a' && c <= 'z');
 	else if (is_multibyte && IS_HIGHBIT_SET(c))
 		return true;
-	else if (locale->provider == COLLPROVIDER_ICU)
+	else if (locale->provider != COLLPROVIDER_LIBC)
 		return IS_HIGHBIT_SET(c) ||
 			(c >= 'A' && c <= 'Z') || (c >= 'a' && c <= 'z');
-	else if (locale->provider == COLLPROVIDER_LIBC)
-		return isalpha_l((unsigned char) c, locale->info.lt);
 	else
-		return isalpha((unsigned char) c);
+		return isalpha_l((unsigned char) c, locale->info.lt);
 }
 
 
-- 
2.34.1

