[dev.cc] code review 172510043: runtime: fix GODEBUG processing

runtime: fix GODEBUG processing

Right now it fails with:

    $ GODEBUG="allocfreetrace=1,efence=1" `which go`
    Segmentation fault: 11

It appears there's a bug in the initialization order of
global variables. dbgvars is initialized before debug,
even though dbgvars references fields of debug, like
debug.allocfreetrace. This caused dbgVar.value to always be 0,
and parsedebugvars to fail when trying to write to it.

Work around this problem by moving dbgvars and its initialization
inside parsedebugvars. This is ok because dbgvars is only used
inside parsedebugvars anyway.

[aram, 2014-11-13 16:26:57]

Hello rsc (cc: brad, dfc, golang-codereviews@googlegroups.com, iant, khr, minux,
r, rlh),

I'd like you to review this change to the dev.cc branch of
https://code.google.com/p/go

[rsc, 2014-11-13 17:31:25]

that's weird. that should be linker initialized.
we should fix that instead of working around it.

[aram, 2014-11-13 17:32:55]

Yes, we should definitely fix that, it probably affects other things as well.

[gobot, 2014-12-19 05:15:52]

R=close

To the author of this CL:

The Go project has moved to Gerrit Code Review.

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