Change the run.go driver to recognize the "gc" build tag.
Change existing tests to use the "gc" build tag if they use some
feature that seems specific to the gc compiler, such as passing specific
options to or expecting specific behavior from "go tool compile".
Change tests to use the "!gccgo" build tag if they use "go build" or
"go run", as while those might work with compilers other than gc, they
won't work with the way that gccgo runs its testsuite (which happens
independently of the go command).
For #43252
Change-Id: I666e04b6d7255a77dfc256ee304094e3a6bb15ad
Reviewed-on: https://go-review.googlesource.com/c/go/+/279052
Trust: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Raising an out-of-bounds panic is confusing. There's no indication
that the underlying problem is a race.
The runtime already does a pretty good job of detecting this kind of
race (modification while iterating). We might as well just reorganize
a bit to avoid the out-of-bounds panic.
Fixes#33275
Change-Id: Icdd337ad2eb3c84f999db0850ec1d2ff2c146b6e
Reviewed-on: https://go-review.googlesource.com/c/go/+/191197
Reviewed-by: Martin Möhrmann <moehrmann@google.com>