Document -Zcache-proc-macros
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Document -Zcache-proc-macros
#151227
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If there isn't one, we should create one and link it from the new page. |
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| ## `cache-proc-macros` | |||
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| This option instructs `rustc` to cache (derive) proc-macro invocations using the incremental system. Note that this can be unsouned - we currently do not check if the macro invocation is actually "cacheable" or not. | |||
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| This option instructs `rustc` to cache (derive) proc-macro invocations using the incremental system. Note that this can be unsouned - we currently do not check if the macro invocation is actually "cacheable" or not. | |
| This option instructs `rustc` to cache (derive) proc-macro invocations using the incremental system. Note that this can be unsound - we currently do not check if the macro invocation is actually "cacheable" or not. |
also, about the "we currently do not check" part, is the plan is to infer whether the proc-macro is cacheable (seems unlikely), or rather respect what the user promises about its behavior? This could just mention that enabling the flag for proc-macros that are not pure functions is bound to reuse stale extensions.
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Forgot about this in #145354.