> On 17 Apr 2025, at 01:28, Tom Lane <t...@sss.pgh.pa.us> wrote: > > Jacob Champion <jacob.champ...@enterprisedb.com> writes: >> On Wed, Apr 16, 2025 at 4:04 PM Tom Lane <t...@sss.pgh.pa.us> wrote: >>> Looking through all of the callers of freeJsonLexContext, quite >>> a lot of them use local JsonLexContext structs, and probably some >>> of them are more performance-critical than these. So that raises >>> the question of why are we seeing warnings for only these call >>> sites? > >> Yeah, I had the same question... > > After making another pass through the callers of freeJsonLexContext, > I observe that the warnings appear in callers that use a local > variable *and* contain goto statements. So I'm betting that the > presence of goto's causes the LTO optimizer to pull in its horns > quite a bit and thereby fail to detect the flag correlation.
That seems plausible given the selective warnings. >>> Maybe there is a more elegant way to suppress them. > >> Can we brute-force ignore this particular warning site with a #pragma >> (suggested in [1])? > > That's surely not elegant :-(. However, I don't especially want to > rewrite away the goto's in these callers ... Agreed, moving to heap allocated structures for these callsites seem much better. Something like the attached should be enough I think? -- Daniel Gustafsson
0001-Allocate-JsonLexContexts-on-the-heap-to-avoid-warnin.patch
Description: Binary data
