Garbage collection, and practical strategies to avoid allocation

[Adam D. Ruppe]

just to toss in my quick thoughts, I wrote a couple comments on 
the recent reddit thread about using D with a minimal runtime and 
some of the talk may be relevant here too:

http://www.reddit.com/r/programming/comments/1fc9jt/dmd_2063_the_d_programming_language_reference/ca94mek


Some little things we could do is add overloads to some functions 
that return string to be able to take a buffer argument too.

string to(T:string)(int a) { char[] buf = new char[](16); return 
assumeUnique(to(a, buffer));

char[] to(int a, char[] buffer) { deposit it straight into 
buffer, return the slice into buffer that is actually used; }


and so on for all kinds of functions. Kinda a pain in the butt 
but when you need it, you have the second variant, and if you 
don't care, the convenient first one is still available (also 
avoids breaking code!)


I also mentioned on irc yesterday that I think a good, low cost 
idea to help find allocations is to add a global flag to druntime 
that makes gc_malloc throw an Error. Then you can set this flag 
in a critical section of code and at least get a runtime notice 
of a missed allocation in testing while still having the gc for 
the rest of the app.

Another member also suggested you can do that easily enough by 
running the program in a debugger and setting a breakpoint at 
gc_malloc, but I think the flag would be simpler yet.