add solaris sparcv9 support

[binarycrusader]

Fixes#39901

[rust-highfive]

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[binarycrusader]

Please note that this pull request depends upon another pull request #39871 to actually function as expected.

[binarycrusader]

Note that there is little point in ever using -fomit-frame-pointer on sparc since the sparc ABI requires a minimum of 176 bytes of stack frame, which means space is always reserved for %fp regardless of whether it's used. Also, most debuggers and other tools on any platform for sparc generally expect %fp to be valid.

[eddyb]

r? @alexcrichton

[alexcrichton]

Looks good to me, thanks! Out of curiosity, would sparc64-sun-solaris be "wrong", or is sparcv9 just conventional?

[binarycrusader]

SPARC v9 (as in version 9) is the official name of the 64-bit architecture and is what is always used on Solaris and in SPARC architecture documentation. The ELF ABI documentation also refers to it as sparcv9. The C compilers also set __sparcv9 to be defined. For reasons unknown to me, the BSDs have always used sparc64 instead.

So, at least on Solaris, it would be unexpected and surprising to refer to it as sparc64.

[binarycrusader]

GCC built on Solaris and LLVM built on Solaris also refer to it as sparcv9 for this reason.

[alexcrichton]

Ok, sounds good to me, thanks!

@bors: r+

I wonder though if we should rename the target_arch = "sparc64" cfg? If the official name is sparcv9 it may be best to use that name

[bors]

📌 Commit 2e756e2 has been approved by alexcrichton

[bors]

⌛ Testing commit 2e756e2 with merge 83815d9...

[bors]

💔 Test failed - status-appveyor

[alexcrichton]

@bors: retry * network error

…

On Sun, Feb 19, 2017 at 12:30 AM, bors ***@***.***> wrote: 💔 Test failed - status-appveyor <https://ci.appveyor.com/project/rust-lang/rust/build/1.0.2024> — You are receiving this because you were assigned. Reply to this email directly, view it on GitHub <#39903 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AAD95Bh8S35IYQmHcjvcFbf_auYQ7mvqks5rd-GMgaJpZM4MD5O2> .

[binarycrusader]

As an FYI, the frame pointer bug on sparc turned out to be an old oversight in gcc; a bug was filed and the issue fixed for future gcc versions. I'd still heavily discourage use of -fomit-frame-pointer on sparc for some of the reasons I previously mentioned.