diff mbox series

[v2,13/13] libc: mips: fix strcmp bug for little endian targets

Message ID 20250402141228.1973965-14-jovan.dmitrovic@htecgroup.com
State New
Headers
Series A series of updates related to MIPS |

Commit Message

Jovan Dmitrovic April 2, 2025, 2:14 p.m. UTC 
  From: Faraz Shahbazker <fshahbazker@wavecomp.com>

strcmp gives incorrect result for little endian targets under
the following conditions:
1. Length of 1st string is 1 less than a multiple of 4 (i.e len%4=3)
2. First string is a prefix of the second string
3. The first differing character in the second string is extended
ASCII (that is > 127)
---
 newlib/libc/machine/mips/strcmp.S | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/newlib/libc/machine/mips/strcmp.S b/newlib/libc/machine/mips/strcmp.S
index 126344d6c..07b988a57 100644
--- a/newlib/libc/machine/mips/strcmp.S
+++ b/newlib/libc/machine/mips/strcmp.S
@@ -217,10 +217,13 @@  L(worddiff):
 	beq	a0, zero, L(wexit01)
 	bne	a0, a1, L(wexit01)
 
-	/* The other bytes are identical, so just subract the 2 words
-	  and return the difference.  */
+# if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
+	srl a0, a2, 24
+	srl a1, a3, 24
+# else /* __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__ */
 	move a0, a2
 	move a1, a3
+# endif /* __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__ */
 
 L(wexit01):
 	subu	va0, a0, a1