Could you be more specific? The log file is, well, long.

The original failure was in https://build.chromium.org/p/tryserver.chromium.win/builders/win_clang/builds/3139
(logdog: https://luci-logdog.appspot.com/v/?s=bb%2Ftryserver.chromium.win%2Fwin_clang%2F3139%2F%2B%2Frecipes%2Fsteps%2Fcompile__with_patch_%2F0%2Fstdout)

And the failure message was 

FAILED: E:/b/depot_tools/python276_bin/python.exe gyp-win-tool link-wrapper environment.x64 False link.exe /nologo /OUT:ar_sample_test_driver.exe /PDB:ar_sample_test_driver.exe.pdb @ar_sample_test_driver.exe.rsp
LINK : fatal error LNK1201: error writing to program database 'E:\b\build\slave\win_clang\build\src\out\Debug_x64\ar_sample_test_driver.exe.pdb'; check for insufficient disk space, invalid path, or insufficient privilege

But that bot seems to be doing fine now. The reason I thought it was odd is because the bot_update step reported a lot of disk space available: `[147GB/249GB used (59%)]`