Fix incorrect parallel build of jsonapi.o with Makefiles. Commit 0785d1b8b wrote
jsonapi_shlib.o: override CPPFLAGS += -DJSONAPI_USE_PQEXPBUFFER forgetting that GNU make treats this change to CPPFLAGS as affecting not only jsonapi_shlib.o, but anything that gets built in pursuit of building jsonapi_shlib.o. Because of an even more ancient hack (cf 7143b3e82), that will include jsonapi.o if it's not been built already. If we do apply this -D switch to jsonapi.o, it gets built with the wrong expansible-string infrastructure, which manifests immediately as a link failure in pg_combinebackup and would misbehave at runtime even if the build somehow completed. Perhaps remarkably, we'd not seen field reports of build failures till now, but it's pretty easy to reproduce a mis-build by trying to build src/common/ with --shuffle and a high -j factor. To fix, don't modify CPPFLAGS this way; instead make a dedicated build rule for jsonapi_shlib.o that injects the additional switches. There might be other places with similar problems, but some desultory attempts with -j32 --shuffle on a 32-thread CPU didn't find any more build failures. Also, it looks like the meson build infrastructure lacks this problem (but I'm no meson expert). Bug: #19727 Reported-by: Ross Burton <[email protected]> Author: Tom Lane <[email protected]> Reviewed-by: Ross Burton <[email protected]> Discussion: https://postgr.es/m/[email protected] Backpatch-through: 18 Branch ------ master Details ------- https://git.postgresql.org/pg/commitdiff/ee089509690eabf3ae1603896652190d3ff41f41 Modified Files -------------- src/common/Makefile | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-)
