Ninja: Fix unrestricted sysconf() returns
As observed in #16740 (closed) , the calculateCommandLineLengthLimit
incorrectly treats -1 returns from sysconf()
calls as numerical -1 whereas it represents an undefined limit, i.e. infinity.
Given this value is only defined for limit queries, it should be only needed for the query to _SC_MAX_ARG
.
Fixes: #16740 (closed)
Topic-rename: ninja-fix-sysconf-non-limit