Eliminated warnings in Visual Studio 2019. #96
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The Microsoft C/C++ compiler warned about possibly
writing too much memory in lines like this:
memset(scratch.grbuf[0], 0, 576*2*sizeof(float));
Although the code is correct, it confuses the compiler
into thinking more memory is being zeroed out than
intended. scratch.grbuf[0] holds only half as many
bytes as scratch.grbuf, but the code intends to
zero out the entire array, not just the first half.
Replaced with identical code that eliminates
the warning:
memset(scratch.grbuf, 0, sizeof(scratch.grbuf));
This is also easier to understand and verify as correct.
The Visual Studio 2019 C/C++ compiler reported
a warning that the following array accesses in
L3_stereo_process could go out of bounds:
kl = g_pan[2*ipos];
kr = g_pan[2*ipos + 1];
The compiler apparently believes that the
value of the expression `HDR_TEST_MPEG1(hdr)`
could change its value when evaluated more than once,
even though it is clear from the code that the header
data is constant. The compiler's false theory results
in a perceived risk of reading outside the array
bounds of `g_pan`.
By explicitly evaluating `HDR_TEST_MPEG1(hdr)`
exactly once and holding its value in a local
variable, the warning disappears.
cosinekitty
changed the title
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The Microsoft C/C++ compiler warned about possibly
writing too much memory in lines like this:
Although the code is correct, it confuses the compiler
into thinking more memory is being zeroed out than
intended. scratch.grbuf[0] holds only half as many
bytes as scratch.grbuf, but the code intends to
zero out the entire array, not just the first half.
Replaced with identical code that eliminates
the warning:
This is also easier to understand and verify as correct.