From 554d2edfb94c001eb0818d3325340e5db61f4bd2 Mon Sep 17 00:00:00 2001 From: Nikhil Benesch Date: Sun, 16 Jul 2017 23:14:19 -0400 Subject: [PATCH] build: update stale comment about build artifact caching h/t @tschottdorf --- build/common.mk | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-) diff --git a/build/common.mk b/build/common.mk index db3c7220417c..ae44888c0d71 100644 --- a/build/common.mk +++ b/build/common.mk @@ -344,12 +344,11 @@ $(CGO_FLAGS_FILES): $(REPO_ROOT)/build/common.mk # marker file when switching between revisions that span the change. For # simplicity, just sequentially bump the version number within. # -# NB: the recipes below nuke *all* build artifacts when a dependency's source -# tarball changes. Normally, we could rely on the dependency's build system to -# detect modified files and only rebuild the necessary objects, but tar assigns -# extracted files their original modification time (i.e., a time well in the -# past, when the tarballs were packaged), and so the build artifacts always look -# up-to-date. +# NB: the recipes below nuke *all* build artifacts when a dependency's configure +# flags change. In theory, we could rely on the dependency's build system to +# only rebuild the affected objects, but in practice dependencies on configure +# flags are not tracked correctly, and these stale artifacts can cause +# particularly hard-to-debug errors. $(JEMALLOC_SRC_DIR)/configure.ac: $(BOOTSTRAP_TARGET)