Segmentation fault with -O3 and -flto with GCC 8.3.0 and newer

[marxin]

As analyzed in GCC bug report, I suspect nodejs violates aliasing rules:
https://github.com/nodejs/node/blob/master/src/node_platform.cc#L397

[bnoordhuis]

Thanks for the report. Node.js is normally built with -fno-strict-aliasing for this reason, see the list of compiler flags in common.gypi.

It seems the reporter of the GCC bug explicitly overrode that but that's not a supported configuration so I'll go ahead and close this out.

[marxin]

Thanks for the report. Node.js is normally built with -fno-strict-aliasing for this reason, see the list of compiler flags in common.gypi.

Heh, knowing that, it would save some time for me :)
Btw. are you considering removal of the -fno-strict-aliasing? Note that you're paying by performance..

[bnoordhuis]

V8, the Javascript engine, relies heavily on techniques that are not strict-aliasing safe. Fixing that has been discussed since at least 2010 and it's 2019 now so I don't think it'll happen anytime soon. :-)

[emerzon]

I have the exact same issue just by enabling lto (--enable-lto). I am not messing around with -fno-strict-aliasing.

[addaleax]

@emerzon Since you are not changing compiler flags, it’s likely a different underlying problem – can you open a new bug report, fill out the details (esp. system information + maybe compile version), and the steps that you used to reproduce?