build(linux): fix compilation with Clang #3998
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Pull Request Overview
This PR fixes a Clang compilation error by replacing inline initialization of variable-length arrays with explicit memset zeroing.
- Removed direct initializer usage for VLAs and added memset calls to clear memory.
- Applied the same fix to both iovs and msgs arrays in different code blocks.
Comments suppressed due to low confidence (2)
src/platform/linux/misc.cpp:427
- Consider adding a short inline comment explaining that memset is used here to zero initialize the variable-length array because direct initializer lists are not supported by Clang.
struct iovec iovs[(send_info.headers ? std::min(seg_max, send_info.block_count) : 1) * max_iovs_per_msg];
src/platform/linux/misc.cpp:511
- Similarly, add a brief comment alongside the memset calls for msgs and iovs to clarify that this approach is a workaround for Clang's limitations with variable-length array initialization.
struct mmsghdr msgs[send_info.block_count];
Clang 20.1.7 fails with the following error:
```
/var/tmp/portage/net-misc/sunshine-2025.122.141614/work/Sunshine-2025.122.141614/src/platform/linux/misc.cpp:427:25: error: variable-sized object may not be initialized
427 | struct iovec iovs[(send_info.headers ? std::min(seg_max, send_info.block_count) : 1) * max_iovs_per_msg] = {};
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
```
As VLAs are not part of the C++ standard, Clang barely support of their features. However, simple memset fixes the issue.
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Bundle ReportBundle size has no change ✅ |
Codecov ReportAttention: Patch coverage is
Additional details and impacted files@@ Coverage Diff @@
## master #3998 +/- ##
==========================================
- Coverage 11.37% 11.37% -0.01%
==========================================
Files 92 92
Lines 17549 17553 +4
Branches 8232 8231 -1
==========================================
Hits 1996 1996
+ Misses 14868 13037 -1831
- Partials 685 2520 +1835
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|
Thanks for the contribution. I'm going to just remove the zeroing in #4052 since it's a bit overzealous anyway. |
Description
Clang 20.1.7 fails with the following error:
As VLAs are not part of the C++ standard, Clang barely supports their features. However, simple memset fixes the issue.
Issues Fixed or Closed
Type of Change
.github/...)Checklist