On 16.07.2019 23:18, Rainer Jung wrote: > I had some need for using APR_POOL_DEBUG today and ran into a > situation where pool lifetimes needed a hint using apr_pool_join(). > That is all documented and fine, except that I was surprised to see, > that apr_pool_join() doesn't work unless the application itself is > also compiled with APR_POOL_DEBUG. I think that's not the intend, one > should be able to replace the apr library against a debug one during > lifetime. > > So IMHO apr_pool_join() in apr has to be a noop function when > APR_POOL_DEBUG is not defined, so that the function call is contained > in the application. > > Currently when the app is compiled without APR_POOL_DEBUG, then in > apr.h we only have > > #if APR_POOL_DEBUG || defined(DOXYGEN) > ... > #else /* APR_POOL_DEBUG or DOXYGEN */ > > #ifdef apr_pool_join > #undef apr_pool_join > #endif > #define apr_pool_join(a,b) > ... > #endif /* APR_POOL_DEBUG or DOXYGEN */ > > so apr_pool_join() would be an empty macro. > > Other pool debug functions seem to share the same fate: > > - apr_pool_owner_set() > - apr_pool_find() > - apr_pool_num_bytes() > - apr_pool_lock() > - and as mentioned apr_pool_join() > > Any opinion on whether we should introduce empty implementations > instead of empty macros for those all?
What should apr_pool_join and the other pool debugging functions do if you're not debugging pools? They should be no-ops. So replacing them with empty macros makes sense. Or are you arguing that two libapr variants, one compiles with APR_POOL_DEBUG and one without, should be ABI- compatible? -- Brane
