Author Name: Arthur Kahlich
Original Redmine Issue: 1081 from https://www.veripool.org

While I think this is something I can work around, it would be nice if it "just worked".

I took the SystemC example given in the documentation and just changed the verilator command line to:

followed by:

and I get a linker failure as follows:

```verilated_vpi.o: In function vpi_get_time': verilated_vpi.cpp:(.text+0x11e4): undefined reference to sc_time_stamp()'
verilated_vpi.o: In function `vpi_register_cb':
verilated_vpi.cpp:(.text+0x7ea3): undefined reference to `sc_time_stamp()'
collect2: ld returned 1 exit status

The reason for the undefined reference is because verilated_vpi.cpp in this case really needs

```#include "systemc.h"

before the #include "verilated.h" so that the VL_TIME_IQD macros used within it are defined by verilated.h to refer to the SystemC sc_time_stamp() that returns a class instead of the default for non-systemC that returns a double.

This could easily be fixed by adding to $VERILATOR_ROOT/include/verilated.mk a definition of:

VK_CPPFLAGS_WALL += -DVM_SC=$(VM_SC)
endif

and then adding before line 29 of $VERILATOR_ROOT/include/verilated_vpi.cpp :

#include "systemc.h"
#endif