== This Week == TCWG-619: * Compiled chromium on ARM without LTO with following hack to resolve error: undefined reference to 'clock_gettime', version 'GLIBC_2.17' - chromium uses prebuilt sysroot in src/chrome/installer/linux/debian_wheezy_arm-sysroot and it has libc-2.13.so, libc.so.6 is symbolic link to libc-2.13.so in the sysroot. However it appears minimum libc-2.17 is required (version 'GLIBC_2.17'). I replaced libc-2.13.so by abe-built libc-2.20-2014.11-1-git.so, and symlinked libc.so.6 to libc-2.20-2014.11-1-git.so and that worked (for non LTO build). Curiously I didn't require to do this for building chromium with linaro prebuilt toolchain.
* Found a way to disable LTO for building lib/libblink_web.so by manually removing -flto from web_blink.ninja and Webkit/source/core/*.ninja, which worked.
* Chromium non LTO build issues on ARM: a) Fails with gcc-5 due to error in chromium: https://code.google.com/p/chromium/issues/detail?id=340312 To compile chromium, I applied a patch to cp/typeck2.c to shut narrowing conversion errors (ideally the fix should be to chromium).
b) ld.bfd (linaro branch) fails with undefined references to many functions in libattr1: http://pastebin.com/ju4SCDSE Not sure if this is ld.bfd bug, or me building it wrongly. Haven't tested yet with trunk ld.bfd. Works fine with gold.
* Target independent Chromium LTO issues with trunk a) Top-level asm and LTO (PR57703) - This appears to be not supported.
* Chromium LTO issues on ARM with trunk: a) ICE in lib/libblink_web.so (PR65576). b) Target specific builtin not available: http://pastebin.com/2ANsEyMn Seems related to: https://code.google.com/p/chromium/issues/detail?id=408997 c) ICE during LINK chrome: http://pastebin.com/DpjJ5M7g d) GNU ld appears to segfault compiling in LTO mode.
* Chromium LTO issues with linaro-4.9 branch: a) ICE elf section out of range (PR57208) - fixed in trunk b) gold - Ran out of file descriptors: fixed in trunk. Seems the following patch which is in trunk but not in linaro branch fixes it: https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git%3Ba=blobdiff%3Bf=go... I tried to backport it but got errors, possibly depends on other commits.
* v8 ARM LTO issues: - Assembly error - offset out of range (PR65778). Possibly invalid bug.
== Next Week == - Create reduced test case for PR65576 - Figure out how to disable LTO for building lib/libblink_web.so in .gyp files - PR49551 - Exams on 20th and 24th April.