Why doesn't Ada have a garbage collector?

Question

I know GC wasn't popular in the days when Ada was developed and for the main use case of embedded programming it is still not a good choice.

But considering that Ada is a general purpose programming language why wasn't a partial and optional (traces only explicitly tagged memory objects) garbage collector introduced in later revisions of the language and the compiler implementations.

I simply can't think of developing a normal desktop application without a garbage collector anymore.

Answer 1

Ada was designed with military applications in mind. One of the big priorities in its design was determinism. i.e. one wanted an Ada program to consistently perform exactly the same way every time, in any environment, under all operating systems... that kinda thing.

A garbage collector turns one application into two, working against one another. Java programs develop hiccups at random intervals when the GC decides to go to work, and if it's too slow about it there's a chance that an application will run out of heap sometimes and not others.

Simplified: A garbage collector introduces some variability into a program that the designers didn't want. You make a mess - you clean it up! Same code, same behavior every time.

Not that Ada became a raging worldwide success, mind you.