maint: adjustments to recent timeout change

* .gitignore: Add /lib/fenv.h to ignore list.
* tests/timeout/timeout-parameters.sh: Use a sleep length of 10s
to be consistent with the pattern where we use this larger time
when it does not slow down a test, but also provides protection
against a hung test, and better avoidance of false failures due
to races on very loaded systems.  Also fix the setting of FAIL.
* tests/timeout/timeout-large-parameters.sh: Remove duplicated test.

.gitignore

@@ -67,6 +67,7 @@
 /lib/errno.h
 /lib/error.h
 /lib/fcntl.h
+/lib/fenv.h
 /lib/float.h
 /lib/fnmatch.h
 /lib/getopt-cdefs.h

tests/timeout/timeout-large-parameters.sh

@@ -43,7 +43,4 @@ timeout 2.34e+5d sleep 0 || fail=1
 timeout $LDBL_MAX sleep 0 || fail=1
 returns_ 125 timeout -- -$LDBL_MAX sleep 0 || fail=1
 
-# Ensure underflow times out immediately
-returns_ 124 timeout 1e-5000 sleep 10 || fail=1
-
 Exit $fail

tests/timeout/timeout-parameters.sh

@@ -41,7 +41,7 @@ timeout 10.34 sleep 0 || fail=1
 timeout 9.999999999 sleep 0 || fail=1
 
 # round underflow up to 1 ns
-returns_ 124 timeout 1e-10000 sleep 1 || fail
+returns_ 124 timeout 1e-10000 sleep 10 || fail=1
 
 # invalid signal spec
 returns_ 125 timeout --signal=invalid 1 sleep 0 || fail=1