pkg/proc: update riscv64 support and fix several tests

[lrzlin]

This pull request adds support for stack-switching functions, contextregnum and sigtramp on riscv64, which fix TestCgoStacktrace, TestCgoStacktrace2, TestStepIntoCoroutine, TestCapturedVarVisibleOnFirstLine and TestDWZCompression.

[aarzilli]

The tests on linux/riscv64 aren't passing because there is no capslock file. Do you mind generating it with

capslock -goos linux -goarch riscv64 -packages ./cmd/dlv > _scripts/capslock_linux_riscv64-output.txt

Also, while we are at this, the linux/riscv64/tip fails due to a timeout compiling go-tip. I think we should just remove it from the test matrix (we don't test tip on linux/386 and linux/pcc64le either).

[lrzlin]

The tests on linux/riscv64 aren't passing because there is no capslock file. Do you mind generating it with

capslock -goos linux -goarch riscv64 -packages ./cmd/dlv > _scripts/capslock_linux_riscv64-output.txt

Added, BTW I have to add GOFLAGS="-tags=exp.linuxriscv64" to generate this, is that okay?

Also, while we are at this, the linux/riscv64/tip fails due to a timeout compiling go-tip. I think we should just remove it from the test matrix (we don't test tip on linux/386 and linux/pcc64le either).

Removed, also I'm wondering with CI machine and renewed support, could we start discussing remove the experimental mark of riscv64 support?

[aarzilli]

Added, BTW I have to add GOFLAGS="-tags=exp.linuxriscv64" to generate this, is that okay?

Yes. You also need to add it to TestCapsLock, the same as the if statement for linux/ppc64le.

Removed, also I'm wondering with CI machine and renewed support, could we start discussing remove the experimental mark of riscv64 support?

Yes.

[lrzlin]

Added, BTW I have to add GOFLAGS="-tags=exp.linuxriscv64" to generate this, is that okay?

Yes. You also need to add it to TestCapsLock, the same as the if statement for linux/ppc64le.

Added, thanks for the guide.

[aarzilli]

LGTM