Re:For Better Computing, Liberate CPUs from Garbage Collection
by irq11 on Thursday May 09, 2019 @04:14PM
(#19871940)
”If you're storing a reference on the heap somewhere, you suddenly have dynamic lifetimes with indeterminate reference counts, and it gets quite hard to 1) correctly manage memory and 2) verify that you're correctly managing memory.”
It is axiomatic that GC programs leak memory. I’ve never encountered one that didn’t. The difference is that it’s harder to see, and most programmers who have grown up with GC systems don’t know how to fix it.
”The alternative is that in all three instances in a GC language, I don't have to care about memory management.”
Again, no. The alternative is thar you aren’t paying attention, and don’t see the leaks until they become fatal. Just like cockroaches, you have them, somewhere.
Wherever you're storing the reference, you have to eventually free the memory. That propagates memory-management code throughout your codebase, and is error-prone.
I totally agree that if you're allocating on the stack it's a non-issue. If you're returning a reference and always freeing in the caller, that's pretty easy too, but you have to have that logic in every single caller. If you're storing a reference on the heap somewhere, you suddenly have dynamic lifetimes with indeterminate reference counts, and it gets quite hard to 1) correctly manage memory and 2) verify that you're correctly managing memory.
The alternative is that in all three instances in a GC language, I don't have to care about memory management. Barring unusual edge cases, I can't forget to deallocate something and end up with a memory leak.