user/spack: (ppc) FTTFS: error: 'mcontext_t' {aka 'struct <anonymous>'} has no member named 'uc_regs'
This is not a Spack-as-a-package problem, but in building libsigsegv, a package that Spack provides, which is used as a test for this package.
See also: #443 (closed), #522 (closed), #671 (closed).