On Thursday, 18 September 2014 at 16:48:22 UTC, Scott Wilson
wrote:
Unit of compilation is one D file but I saw if I pass several D
files to the compiler only one .o file is generated. Whats the
story there.
DMD will generate one object file per module file, unless you use
the -of option. With -of, the compiler will compile all module
files to a single object file.
Plus if I change a non template function in one module then
theres no way to tell make no rebuild of modules importing it.
The dmd -deps call seems to generate all recursively. In
gcc/makedepend if one function changes only relinking is needed
or nothing if dynamic loading.
Yes, currently any changes, including function bodies, cause a
rebuild of importing modules. One reason for this is CTFE -
changing a function body can affect the code in importing modules
if they invoke the function during compilation. You could use .di
files to separate declarations from implementations.
Overall as far as I understand compiler is fast but dependency
mgmt is coarse. Also whats the deal with cyclic dependencies. I
saw discussion that its not possible but wrote a few test
modules
and it works fine.
Cyclic dependencies between modules which all have module or
static constructors are forbidden, because it is unknown in which
order the constructors are expected to run.
