Re: JIT compiling with LLVM v11

Andres Freund <andres(at)anarazel(dot)de> writes:
> On 2018-03-13 15:29:33 -0700, Andres Freund wrote:
>> On 2018-03-14 10:32:40 +1300, Thomas Munro wrote:
>>> It looks
>>> like -fexcess-precision-standard is coming from a configure test that
>>> was run against ${CC}, not against ${CLANG}, so I hacked the generated
>>> src/Makefile.global to remove that too, just to see if I could get
>>> past that.

>> Yea, I'd hoped we could avoid duplicating all the configure tests, but
>> maybe not :(.

> I've mostly done that now (not pushed). I've created new
> PGAC_PROG_VARCC_VARFLAGS_OPT(compiler variable, flag variable, testflag)
> function, which now is used to implement PGAC_PROG_CC_CFLAGS_OPT and
> PGAC_PROG_CC_VAR_OPT (similar for CXX). That makes it reasonable to
> test the variables clang recognizes separately.

Meh. I agree with Thomas' concern that it's not clear we can or should
just ignore discrepancies between the -f options supported by the C
and CLANG compilers.

Is it really so necessary to bring a second compiler into the mix for
this? Why not just insist that JIT is only supported if the main build
is done with clang, too? My experience with mixing results from different
compilers is, eh, not positive.

regards, tom lane