admin/webrtc_m130
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Fix C4434 warning about 32-bit shift assigned to 64-bits

Browse Source 
VS 2015 has a new or louder warning about 32-bit shifts that are then
assigned to a 64-bit target. This type of code triggers it:

int64_t size = 1 << shift_amount;

Because the '1' being shifted is a 32-bit int the result of the shift
will be a 32-bit result, so assigning it to a 64-bit variable is just
misleading.

In this case the code that triggers it is this:

  size_t window_size = static_cast<size_t>(1 << shift_amount);

The destination is a size_t so the warning only shows up on 64-bit
builds and doesn't indicate a real bug. It's curious that the code
had a cast already - presumably to suppress some other warning - but
the cast is not in the ideal place and doesn't avoid this new warning.
Moving the cast allows shift_amount to be log2(size_t) and allows
enabling C4334 in Chromium.

BUG=593448

Review URL: https://codereview.webrtc.org/1849753004

Cr-Commit-Position: refs/heads/master@{#12199}
This commit is contained in:
brucedawson 2016-04-01 10:16:14 -07:00 committed by Commit bot
parent fa0befe13b
commit d81dc49c5b
1 changed files with 1 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
webrtc/modules/audio_processing/intelligibility/intelligibility_enhancer.cc
View File

@ -93,7 +93,7 @@ IntelligibilityEnhancer::IntelligibilityEnhancer(int sample_rate_hz,
43.f));
start_freq_ = std::max(static_cast<size_t>(1), erb_index * kErbResolution);
size_t window_size = static_cast<size_t>(1 << RealFourier::FftOrder(freqs_));
size_t window_size = static_cast<size_t>(1) << RealFourier::FftOrder(freqs_);
std::vector<float> kbd_window(window_size);
WindowGenerator::KaiserBesselDerived(kKbdAlpha, window_size,
kbd_window.data());