Fix use of equality of value_sett::object_mapt

[romainbrenguier]

This was removed recently in pull request #4694 but it
seems necessary when compiling with clang which would complain about it
not being defined.

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[smowton]

I assume this is a fix for #4699 ? If so, note that in the commit message and add a comment that this is a pointless specialisation of https://github.com/diffblue/cbmc/blob/develop/src/util/reference_counting.h#L185 which we supply to tolerate old broken compilers.

[romainbrenguier]

@smowton

I assume this is a fix for #4699 ? If so, note that in the commit message and add a comment that this is a pointless specialisation of https://github.com/diffblue/cbmc/blob/develop/src/util/reference_counting.h#L185 which we supply to tolerate old broken compilers.

Yes, I have added that to the commit message. I also changed a bit the code so that we don't redefine the equality function.

[smowton]

Shame to throw away the reference-equal case though? If you're going to inline reference_countingt::operator== then inline the whole thing

[allredj]

✔️
Passed Diffblue compatibility checks (cbmc commit: 8cd09b3).
Build URL: https://travis-ci.com/diffblue/test-gen/builds/113132139

[romainbrenguier]

@smowton

Shame to throw away the reference-equal case though? If you're going to inline reference_countingt::operator== then inline the whole thing

this is now fixed

[smowton]

Add a comment noting that this is a copy of (link to reference_countingt::operator==) and noting why this was done

[allredj]

We're fixing something for clang 3.8, but we're not compiling with clang 3.8 on CI. So this (or something similar) will probably break later and we'll waste more time. Should we not add another build on CI?

[romainbrenguier]

@allredj

We're fixing something for clang 3.8, but we're not compiling with clang 3.8 on CI. So this (or something similar) will probably break later and we'll waste more time. Should we not add another build on CI?

pull request to add the CI step: #4718

[allredj]

✔️
Passed Diffblue compatibility checks (cbmc commit: b27ceb9).
Build URL: https://travis-ci.com/diffblue/test-gen/builds/113404218