This allows skipping/overriding the OSSH_CHECK_CFLAG_COMPILE and
OSSH_CHECK_CFLAG_LINK macros used to discover supported compiler
or linker flags. E.g.
$ ./configure ossh_cv_cflag__fzero_call_used_regs_used=no
[...]
checking if cc supports compile flag -ftrapv and linking succeeds... yes
checking if cc supports compile flag -fzero-call-used-regs=used and linking succeeds... (cached) no
checking if cc supports compile flag -ftrivial-auto-var-init=zero... yes
Patch from Colin Watson, ok dtucker@
Damien Miller
29cf521486