When the -V flag is passed to the iverilog command, we can easily
print the version information for the driver itself, but it is also
valuable to probe all the components that would have been used for
a real compile. So the driver executes the preprocessor and the ivl
core to have them print version information.
The ivl core program also tries to load the target code generator
and get version information to print. For this to work, create a new
optional entry point "target_query" that takes a query key string as
an argument and returns a const string as the result. Use this with
the key "version" to get version information out of the target.
Target selection is done by the DLL target code generator, so there
is no value having a layer of target selection ahead of it. Remove
all that redundant code and simplify the target config files to reflect
this.
The MinGW system() implementation appears to return the straight
return value instead of the waitpid() like result that more
normal systems return. Because of this just return the system()
result without processing for MinGW compilations.
Older version of the MinGW runtime (pre 3.14) just used the
underlying vsnprintf(). Which has some problems. The 3.14 version
has some nice improvements, but it has a sever bug when processing
"%*.*f", -1, -1, <some_real_value>. Because of this we need to use
the underlying version without the enhancements for now.
snprintf prints %p differently than the other printf routines
so use _snprintf to get consistent results.
Only build the PDF files if both man and ps2pdf exist.
MinGW does not know about the z modifier for %d, %u, etc.
Add some missing Makefile check targets.