Building clang with gcc-toolchain@11

[Greg Hogan <code@greghogan.com>]

[-- Attachment #1: Type: text/plain, Size: 3185 bytes --]

When creating a profile containing both clang-toolchain and gcc-toolchain I
see the same issue as in #43023; however, if I specify the default
gcc-toolchain (currently gcc-toolchain@10) then clang and gcc work just
fine together.

--8<---------------cut here---------------start------------->8---
$ guix time-machine --commit=0dc99fd1 -- shell --container gcc-toolchain@10
clang-toolchain coreutils grep
$ env | grep CPLUS_INCLUDE_PATH
CPLUS_INCLUDE_PATH=/gnu/store/4nd3abfcmf1zdqgrvi94ymwwijad9rkq-profile/include/c++:/gnu/store/4nd3abfcmf1zdqgrvi94ymwwijad9rkq-profile/include
$ g++ hello.cpp && ./a.out
Hello World!
$ clang++ hello.cpp && ./a.out
Hello World!
--8<---------------cut here---------------end--------------->8---

This is nice, but necessitates use of an old version of GCC until such time
as core-updates is updated then eventually merged.

I'd like to instead use the latest gcc-toolchain (currently gcc-toolchain@11)
and have clang-toolchain built with that gcc-toolchain. No matter what
I offer in the "--with-c-toolchain" or "--with-input" options I always see
the following error regarding '(assoc-ref %build-inputs "libc")' evaluating
as false, even when specifying "--with-c-toolchain=clang=gcc-toolchain@10"
that should currently be in use by default. Any ideas for fixing this?

Thanks,
Greg


--8<---------------cut here---------------start------------->8---
$ ./pre-inst-env guix build clang --with-c-toolchain=clang=gcc-toolchain@11
The following derivation will be built:
   /gnu/store/7da3w2r437f78q22rqxnqzpcv13fhrfb-clang-13.0.1.drv
building /gnu/store/7da3w2r437f78q22rqxnqzpcv13fhrfb-clang-13.0.1.drv...
Backtrace:
          14 (primitive-load "/gnu/store/8qmqddxxzgfvvslwffm9xwfay7a?")
In ice-9/eval.scm:
   214:21 13 (_ #f)
   217:50 12 (lp (#<procedure 7ffff4bff920 at ice-9/eval.scm:282:?> ?))
   217:50 11 (lp (#<procedure 7ffff4bff900 at ice-9/eval.scm:282:?> ?))
   217:50 10 (lp (#<procedure 7ffff4bff8a0 at ice-9/eval.scm:649:?> ?))
   217:50  9 (lp (#<procedure 7ffff4bff880 at ice-9/eval.scm:282:?> ?))
   217:50  8 (lp (#<procedure 7ffff4bff820 at ice-9/eval.scm:649:?> ?))
   217:50  7 (lp (#<procedure 7ffff4bff800 at ice-9/eval.scm:282:?> ?))
   217:50  6 (lp (#<procedure 7ffff4bff7e0 at ice-9/eval.scm:282:?> ?))
   217:50  5 (lp (#<procedure 7ffff4bff7c0 at ice-9/eval.scm:282:?> ?))
   217:50  4 (lp (#<procedure 7ffff4bff580 at ice-9/eval.scm:649:?> ?))
   217:50  3 (lp (#<procedure 7ffff4bff560 at ice-9/eval.scm:282:?> ?))
   217:33  2 (lp (#<procedure 7ffff4b91660 at ice-9/eval.scm:202:?> ?))
   202:51  1 (_ #f)
In unknown file:
           0 (string-append "-DC_INCLUDE_DIRS=" #f "/include")

ERROR: In procedure string-append:
In procedure string-append: Wrong type (expecting string): #f
builder for `/gnu/store/7da3w2r437f78q22rqxnqzpcv13fhrfb-clang-13.0.1.drv'
failed with exit code 1
build of /gnu/store/7da3w2r437f78q22rqxnqzpcv13fhrfb-clang-13.0.1.drv failed
View build log at
'/var/log/guix/drvs/7d/a3w2r437f78q22rqxnqzpcv13fhrfb-clang-13.0.1.drv.gz'.
guix build: error: build of
`/gnu/store/7da3w2r437f78q22rqxnqzpcv13fhrfb-clang-13.0.1.drv' failed
--8<---------------cut here---------------end--------------->8---

[-- Attachment #2: Type: text/html, Size: 3963 bytes --]