Win32: couple of platform detection fixes #457
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Is there a support claim to use a pointer-sized value? BTW, personally, I find the "platform word" guidance provided by comment NGX_ALIGNMENT is used to align ngx_palloc() sub-allocations from pool memory Effectively, this is what you do here by operating a pointer-sized value,
Unix-like 64-bit systems ?
The impact here appears that ngx_palloc() alignment might |
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Previously, the default pool alignment used sizeof(unsigned long), with the expectation that this would match to a platform word size. Certain 64-bit platforms prove this assumption wrong by keeping the 32-bit long type, which is fully compliant with the C standard. This introduces a possibility of suboptimal misaligned access to the data allocated with ngx_palloc() on the affected platforms, which is addressed here by changing the default NGX_ALIGNMENT to a pointer size. As we override the detection in auto/os/conf for all the machine types except x86, and Unix-like 64-bit systems prefer the 64-bit long, the impact of the change should be limited to Win64 x64.
This extends the target selection implemented in dad6ec3 to support Windows ARM64 platforms. OpenSSL support for VC-WIN64-ARM target first appeared in 1.1.1 and is present in all currently supported (3.x) branches. As a side effect, ARM64 Windows builds will get 16-byte alignment along with the rest of non-x86 platforms. This is safe, as malloc on 64-bit Windows guarantees the fundamental alignment of allocations, 16 bytes.
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Looks good. |
See commit messages.
The
NGX_ALIGNMENTone is actually necessary for the Rust bindings to work on any 64-bit Windows; there are optimizations in Rust that may require pointers to be properly aligned, and thus the standard library enforces this with assertions.The ARM64 stems from the same source, while debugging ^ I found that we pass incorrect configuration template to the OpenSSL;
VC-WIN64-ARMis whatConfigurewould pick without our meddling. Also, having an accurateNGX_MACHINEvalue helps when I needed to guess a target triple.For reference, cl.exe version strings:
Microsoft (R) C/C++ Optimizing Compiler Version 19.16.27051 for ARM64(2017, first available ARM64 toolchain)Microsoft (R) C/C++ Optimizing Compiler Version 19.42.34435 for ARM64(2022)The change has been verified with OpenSSL 3.0-3.4 in a Win64 cross-compile environment and on a real Windows 11 ARM64 VM.
Fixes #446