From 763c993419a6d59e6d2e1d7d60bc8d23981b5a94 Mon Sep 17 00:00:00 2001
From: Jan Engelhardt <jengelh@inai.de>
Date: Tue, 28 Nov 2023 23:22:58 +0100
Subject: [PATCH] string: resolve testsuite failure with aarch64

Fixes: v4.17-9-g323210d
---
 src/string.c | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/src/string.c b/src/string.c
index 11f3c9f..8e12b4a 100644
--- a/src/string.c
+++ b/src/string.c
@@ -1030,8 +1030,19 @@ EXPORT_SYMBOL unsigned long long HX_strtoull_unit(const char *s,
 			errno = ERANGE;
 			return ULLONG_MAX;
 		}
+		/*
+		 * https://eel.is/c++draft/conv.double#2: values
+		 * unrepresentable in the target type (such as forcing -5.2f
+		 * into a uint) is UB.  Thus check for range and apply the
+		 * negation after the conversion to ULL.
+		 */
+		if (q > ULLONG_MAX) {
+			errno = ERANGE;
+			return ULLONG_MAX;
+		}
+		unsigned long long r = q;
 		errno = 0;
-		return neg ? -q : q;
+		return neg ? -r : r;
 	}
 	if (exponent == 0)
 		exponent = 1000;
-- 
2.43.0