I also made a similar patch here https://www.postgresql.org/message-id/F28283CF-AC9C-4930-9D84-56CD9E105504%40gmail.com. I pretty much did the same thing but I also added postgres_inc to dependency because it cannot find postgres headers inside libpq’s headers. After looking at your patch i have few questions. Is meson.override_dependency(‘libpq’, libpq) really needed? It looks like it does nothing. In flex cmd args you removed —build-dir and —source-dir, was that necessary? Also when I was testing ur patch I couldn’t build libpq because of the problem with include directories of dependency that I mentioned. I attach the result patch with fix which only adds postgres_inc to libpq dependency include_directories to your patch.
libpq.patch
Description: Binary data
> 3 янв. 2026 г., в 07:35, Tristan Partin <[email protected]> написал(а): > > On Sat Aug 30, 2025 at 9:55 AM CDT, Andres Freund wrote: >> Hi, >> >> On 2025-08-30 04:18:05 +0000, Elliot Haisley wrote: >>> While working on another project which needed libpq, I tried building >>> postgres >>> as a subproject to consume a recent version of libpq, and noticed it failed. >>> I've put together a small patch that updates build files to not use >>> the global source root, which allows postgres to be built as a meson >>> subproject. >> >> That makes sense. I however can't apply it just now, the PG 18 code is >> frozen >> until mid of the next week due to the release of 18rc1, and I think this >> should be backpatched. > > I also was working on a project that wanted to use libpq as a subproject > and came up with this independent but similar patch. I chose to develop > it against master. > > I think that if we aim to support this workflow that we should add > a test in the tree somewhere. I am happy to develop one if someone > can direct me to a place where they would like it to live. In theory, > the test could even live as a meson test() in the source tree. > > -- > Tristan Partin > Databricks (https://databricks.com) > <v1-0001-Add-subproject-support-to-the-meson-build.patch>
