On Tuesday, 30 June 2015 at 13:22:10 UTC, rsw0x wrote:
Be aware of the challenges:
Compiling source files separately is slower than passing them
all at once to the compiler.
this is only true for dmd
As far as I understand, the slowdown comes from parsing common
dependencies again and again. Any compiler that doesn't cache the
ASTs should be affected, no?
A quick check with two files that both just import std.stdio
suggests that ldc2 behaves similar to dmd. gdc seems to do things
differently, but it takes relatively long anyway which may
obscure things.
$ time (dmd -c test.d test2.d)
real 0m0.028s
user 0m0.020s
sys 0m0.009s
$ time (dmd -c test.d; dmd -c test2.d)
real 0m0.059s
user 0m0.046s
sys 0m0.013s
$ time (ldc2 -c test.d test2.d)
real 0m0.046s
user 0m0.020s
sys 0m0.025s
$ time (ldc2 -c test.d; ldc2 -c test2.d)
real 0m0.090s
user 0m0.064s
sys 0m0.025s
$ time (gdc -c test.d test2.d)
real 0m0.499s
user 0m0.358s
sys 0m0.138s
$ time (gdc -c test.d; gdc -c test2.d)
real 0m0.499s
user 0m0.342s
sys 0m0.155s
