hspice .alter .del in allcorner sim?

[equman]

I'm working with hapice allcorner simulation and I made an allcorner lib to be invoked.
However,an error appeared after invoke allcorner lib.

The error is :

Terminate called after throwing an instance of 'std::logic error' what() basic_string::_S_construct null not valid.

The following is the allcorner lib.

.lib allcorner
*****TT
.lib ‘filepath’ TT_A
.lib ‘filepath’ TT_B
.alter SS
.del lib filepath’ TT_A
.del lib filepath’ TT_B
.lib ‘filepath’ ss_A
.lib ‘filepath’ ss_B
.endl allcorner