If a C23 compiler is detected, try asking for C17. Branches before 16 can't be compiled with a C23 compiler (see deprecation warnings silenced by commit f9a56e72, and non-back-patchable changes made in 16 by commit 1c27d16e). Test __STDC_VERSION__, and if it's above C17 then try appending -std=gnu17. The test is done with the user's CFLAGS, so an acceptable language version can also be configured manually that way.
This is done in branches 15 and older, back to 9.2, per policy of keeping them buildable with modern tools. Discussion: https://postgr.es/m/87o72eo9iu.fsf%40gentoo.org Branch ------ REL_15_STABLE Details ------- https://git.postgresql.org/pg/commitdiff/f00c401c65afa2cf18f0d67d13eeb382df84c37b Modified Files -------------- configure | 77 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ configure.ac | 20 ++++++++++++++++ 2 files changed, 97 insertions(+)
