make: var-op-shell.mk:32: warning: Command "echo "failed"; (exit 13)" exited with status 13
make: var-op-shell.mk:39: warning: Command "exit 13" exited with status 13
make: var-op-shell.mk:62: warning: "kill $$" exited on a signal
/bin/no/such/command: not found
make: var-op-shell.mk:69: warning: Command "/bin/no/such/command" exited with status 127
stderr
Capturing the output of command "echo '$$$$'"
Global: OUTPUT = $$$$
Global: .MAKEFLAGS =  -r -k -d v -d
Global: .MAKEFLAGS =  -r -k -d v -d 0
Var_Parse: ${UNDEF}y (eval)
Capturing the output of command "echo xy"
Global: OUTPUT_OF_UNDEF = xy
Var_Parse: ${OUTPUT_OF_UNDEF} != "xy" (eval-defined-loud)
Global: .MAKEFLAGS =  -r -k -d v -d 0 -d v -d
Global: .MAKEFLAGS =  -r -k -d v -d 0 -d v -d 0
exit status 0