> [JDK-8247872](https://bugs.openjdk.java.net/browse/JDK-8247872) (upgrade > HarfBuzz to 2.7.2) caused build time to go up with 24 seconds on my reference > linux machine. This was one of the four culprits that caused a 25-30% build > time regression over the last two years. > > The problem here was that the new HarfBuzz code caught really bad behaviour > from gcc when compiling with optimizations. The official HarfBuzz build does > not use any -O flags at all for gcc, so presumably the HarfBuzz team is: > > a) not thinking compiler optimization is important for the performance of > this library, and > b) unaware that their code causes such a headache for gcc. > > (Other compilers fare much better: visual studio makes no difference at all, > and for clang just a small regression was observed.) > > The current optimization level was introduced by > [JDK-8255790](https://bugs.openjdk.java.net/browse/JDK-8255790), which were > really about moving libharfbuzz compilation back into libfontmanager. I could > find no comments/discussion relating to the change of optimization level, so > I assume it was incidental, and just seemed good at the time. > > This patch changes the optimization level to `SIZE` (which is the closest > thing we have to no optimization level) on gcc.
Magnus Ihse Bursie has updated the pull request incrementally with one additional commit since the last revision: Update comment to show we don't care about these files. ------------- Changes: - all: https://git.openjdk.java.net/jdk/pull/7919/files - new: https://git.openjdk.java.net/jdk/pull/7919/files/b491f6fb..99642af3 Webrevs: - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=7919&range=02 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=7919&range=01-02 Stats: 2 lines in 1 file changed: 1 ins; 0 del; 1 mod Patch: https://git.openjdk.java.net/jdk/pull/7919.diff Fetch: git fetch https://git.openjdk.java.net/jdk pull/7919/head:pull/7919 PR: https://git.openjdk.java.net/jdk/pull/7919
