Hi!
[ Upstream commit 208a68c8393d6041a90862992222f3d7943d44d6 ]
On some machines, iio-sensor-proxy was returning all 0's for IIO sensor values. It turns out that the bits_used for this sensor is 32, which makes the mask calculation:
*mask = (1 << 32) - 1;
If the compiler interprets the 1 literals as 32-bit ints, it generates undefined behavior depending on compiler version and optimization level.
Ok, it would be problem if code was like that. But it is not:
@@ -159,9 +159,9 @@ int iioutils_get_type(unsigned *is_signed, unsigned *bytes, unsigned *bits_used, *be = (endianchar == 'b'); *bytes = padint / 8; if (*bits_used == 64)
*mask = ~0;
*mask = ~(0ULL); else
*mask = (1ULL << *bits_used) - 1;
*mask = (1ULL << *bits_used) - 1ULL;
Note 1ULL already being there before the change. AFAICT this does not change anything; 1ULL << foo will already have long long type, so substraction will be long long too.
AFAICT this does not change the binary code at all, so it can't fix a bug...
Best regards,
Pavel