From 6b34fbba9b73e1914d56c2aff96356326002430d Mon Sep 17 00:00:00 2001
From: Mans Rullgard <mans@mansr.com>
Date: Thu, 24 Nov 2011 23:15:59 +0000
Subject: [PATCH] MK(BE)TAG: avoid undefined shifts
Casting the left-most byte to unsigned avoids an undefined
result of the shift by 24 if bit 7 is set. This affects
the rm demuxer.
Signed-off-by: Mans Rullgard <mans@mansr.com>
---
libavutil/common.h | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/libavutil/common.h b/libavutil/common.h
index 9691f5bcf86..7e93a1ab479 100644
--- a/libavutil/common.h
+++ b/libavutil/common.h
@@ -218,8 +218,8 @@ static av_always_inline av_const int av_popcount_c(uint32_t x)
return (x + (x >> 16)) & 0x3F;
}
-#define MKTAG(a,b,c,d) ((a) | ((b) << 8) | ((c) << 16) | ((d) << 24))
-#define MKBETAG(a,b,c,d) ((d) | ((c) << 8) | ((b) << 16) | ((a) << 24))
+#define MKTAG(a,b,c,d) ((a) | ((b) << 8) | ((c) << 16) | ((unsigned)(d) << 24))
+#define MKBETAG(a,b,c,d) ((d) | ((c) << 8) | ((b) << 16) | ((unsigned)(a) << 24))
/**
* Convert a UTF-8 character (up to 4 bytes) to its 32-bit UCS-4 encoded form.
--
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