[bmv2] Type is not convertible to string (inlininer bug?)

[smolkaj]

The following program compiles fine, but simple_switch raises the error

terminate called after throwing an instance of 'std::runtime_error'
  what():  Type is not convertible to string
Aborted (core dumped)

at runtime:

#include <core.p4>
#include <v1model.p4>
typedef standard_metadata_t std_meta_t;

header ipv4_t { }

struct H {
    ipv4_t ipv4;
}

struct M { }

parser ParserI(packet_in pk, out H hdr, inout M meta, inout std_meta_t std_meta) {
    state start {
        transition accept;
    }
}

control VerifyChecksumI(in H hdr, inout M meta) {
    apply { }
}

control ComputeChecksumI(inout H hdr, inout M meta) {
    apply { }
}

control aux(inout M meta, in H hdr) {
    table adjust_lkp_fields {
        key = { hdr.ipv4.isValid() : exact; }
        actions = { NoAction; }
    }

    apply{
        adjust_lkp_fields.apply();
    }

}

control IngressI(inout H hdr, inout M meta, inout std_meta_t std_meta) {
    aux() do_aux;
    apply {
        do_aux.apply(meta, hdr);
    }
}


control EgressI(inout H hdr, inout M meta, inout std_meta_t std_meta) {
    apply { }
}

control DeparserI(packet_out b, in H hdr) {
    apply { }
}

V1Switch(ParserI(), VerifyChecksumI(), IngressI(), EgressI(), ComputeChecksumI(), DeparserI()) main;

The error disappears after inlining aux into IngressI by hand.

[smolkaj]

Fixed.