Bug 622040 – gcc 5.4.0 raises internal compiler errors (unclear bugreport)

• Product: Gentoo Linux
• Status: RESOLVED NEEDINFO

[Description toraboracaveman 2017-06-17 18:05:33 UTC]

now i have 4 build logs with failed attemps to compile/emerge qtwebengine. they last log is associated with a case where i used -j1 and limited my cpu frequency to be less than 1ghz, and i confirmed that cpu temp was around 58c and that it did not generate temperature logging around 58c and that it did not generate temperature logging entries in dmesg or sysctl/journald. there are other build logs too where i used mixtures of more lenient cpu freqs and -j args. i also memtest86+ed with no errors for 2.5 pass, plus i run prime95 for maybe 10-15 minutes with no cpu errors even though temp reached 100c. so i guess memory + cpu are ok. i did 2 things recently: 1) upgraded to the new g++ abi, and 2) moved to systemd + paludis. 

here are all the logs, including the last (build.log4) https://github.com/al-caveman/pastebin

plus, in the same pastebin, you will also find "environment" file, which has the environment stuff when building qtwebengine.

[Comment 1 toraboracaveman 2017-06-17 18:09:53 UTC]

i forgot to describe the 'random shit' aspect. basically, what i remember is this:

1. the internal compiler errors happen at random points when compiling qtwebengine, obviously as you see in the 4 build logs.

2. some times, the compiler freezes, and does nothing. no errors. it also does nothing either. just sitting there as if it's blocked by something. this is my conclusion based on my observation: cpu utilization is 0%.

[Comment 2 toraboracaveman 2017-06-17 18:12:33 UTC]

one more thing i forgot:

these errors are not specific to qtwebengine. this happened with llvm, and ncurses (that i remember).

but somehow the errors were gone with those packages, but somehow lingering with qtwebengine.

my theory is this: gcc is failing randomly with undefined behaviour, and it just happens that qtwebengine is the bloatiest out of all. as a result, i am stuck with qtwebengine (can't get past this), only because it is so bloated that the probability of gcc doing some madness is 1 (some variant of the infinite monkey theorem).

[Comment 3 toraboracaveman 2017-06-17 18:35:59 UTC]

added cpuinfo file in the pastebin.

[Comment 4 Jonas Stein 2017-06-17 18:58:35 UTC]

Please use proper language and write complete sentences with upper and lower case and line breaks. This report is difficult to read.

Please attach the logfiles
https://wiki.gentoo.org/wiki/Bugzilla/Bug_report_guide#Problems_at_build_time

Pastebins are lost and not archived in bugzilla. Hence attach these as individual files please.