Fix shift out of bounds on 32-bit non-fast-path platforms #10941
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This is already done for at least macOS and Linux x86(-64) builds. I don't know about the others. |
The x86-32 build uses a fast path, but when I disabled the fast path I got the following compile error with -Werror: mysqlnd_portability.h:221:95: error: right shift count >= width of type [-Werror=shift-count-overflow] For 32-bit platforms that don't have the fast path, this can cause undefined behaviour at runtime. Some CPUs just mask the shift amount so in those cases you even get wrong results. This is not always found during the build because -Werror is off by default.
kamil-tekiela
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Apr 4, 2024
nielsdos
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* PHP-8.2: [ci skip] NEWS Fix shift out of bounds on 32-bit non-fast-path platforms (#10941)
nielsdos
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Apr 4, 2024
* PHP-8.3: [ci skip] NEWS Fix shift out of bounds on 32-bit non-fast-path platforms (#10941)
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The x86-32 build uses a fast path, but when I disabled the fast path I got the following compile error with -Werror:
mysqlnd_portability.h:221:95: error: right shift count >= width of type [-Werror=shift-count-overflow]
For 32-bit platforms that don't have the fast path, this can cause undefined behaviour at runtime. Some CPUs just mask the shift amount so in those cases you even get wrong results.
This is not always found during the build because -Werror is off by default.