From fe9d54f418973f59ec88ca05489da6df3609811f Mon Sep 17 00:00:00 2001 From: Daniel Hahler Date: Thu, 26 Sep 2019 23:43:49 +0200 Subject: [PATCH] doc: contrib/local.mk.example: include ENABLE_LTO (#11097) Using it takes 30+ additional seconds for me with a ccache-enabled build (43s vs. 12s). While it certainly makes sense to use DEBUG during development, bisecting etc, it should be made clearer what causes this. --- contrib/local.mk.example | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/contrib/local.mk.example b/contrib/local.mk.example index 5a31ded59b..4f7f077999 100644 --- a/contrib/local.mk.example +++ b/contrib/local.mk.example @@ -25,6 +25,12 @@ # # CMAKE_BUILD_TYPE := Debug +# With non-Debug builds interprocedural optimization (IPO) (which includes +# link-time optimization (LTO)) is enabled by default, which causes the link +# step to take a significant amout of time, which is relevant when building +# often. You can disable it explicitly: +# CMAKE_EXTRA_FLAGS += -DENABLE_LTO=OFF + # Log levels: 0 (DEBUG), 1 (INFO), 2 (WARNING), 3 (ERROR) # Default is 1 (INFO) unless CMAKE_BUILD_TYPE is Release or RelWithDebInfo. # CMAKE_EXTRA_FLAGS += -DMIN_LOG_LEVEL=1