[llvm-objcopy] broken for x86_64 4.9 and older

[nickdesaulniers]

copypasta from @nathanchance in ClangBuiltLinux/continuous-integration#164:

https://travis-ci.com/ClangBuiltLinux/continuous-integration/jobs/199950119
https://travis-ci.com/ClangBuiltLinux/continuous-integration/jobs/199950119
https://travis-ci.com/ClangBuiltLinux/continuous-integration/jobs/199950121

llvm-objcopy-9: error: 'firmware/e100/d101m_ucode.bin.ihex': The file was not recognized as a valid object file

Relevant bits of Makefile:

fw-shipped-$(CONFIG_E100) += e100/d101m_ucode.bin e100/d101s_ucode.bin \
			     e100/d102e_ucode.bin
...
quiet_cmd_ihex  = IHEX    $@
    cmd_ihex  = $(OBJCOPY) -Iihex -Obinary $< $@

This was "resolved" upstream by torvalds@5620a0d, which we obviously can't backport. We could apply a local patch that removes the fw-shipped rule in the Makefile or fix llvm-objcopy (if it is even broken).

cc @rupprecht

[rupprecht]

ihex support is coming in D60270, but I haven't had any time in the past few weeks to review it.

[nickdesaulniers]

cool, no rush then; I'll revert the use of llvm-objcopy for our CI for now. I'd prefer to simply add the support then on the LLVM side, since we're so close.

[nathanchance]

D60270 appears to work fine, I just applied it locally to test.

It does appear that it was broken up into reading/writing but I can't find the reading half on Phabricator (which we need).

I was able to apply it locally using these two commands:

curl -LSs 'https://reviews.llvm.org/D60270?id=193910&download=true' | git apply -3 -p0 --directory=llvm --exclude=llvm/tools/llvm-objcopy/CopyConfig.cpp

curl -LSs 'https://reviews.llvm.org/D60270?download=true' | git apply -3 -p0 --directory=llvm --include=llvm/tools/llvm-objcopy/CopyConfig.cpp