Why don’t more people use SPARK?
So Ada and SPARK ended up just catering to the industry that created them, high integrity systems, the kind where people die when an out-of-bounds occurs.
It's been a long time since I programmed in ADA, but the TASK support on the toolchain/system I was a long time ago sucked, and you couldn't climb into it and fix it like you might a standalone C RTOS because it was part of the tooling supplied by a vendor.
Vs with Rust, the borrow checker is fairly portable memory lifetime tracking and reasonably independent of hw architectures.
For me there were two main reasons:
1 - the cost of getting a commercial Ada compiler, much more expensive than most alternatives
2 - initially many though that Ada compilers would be extremely costly to implement. Ironically, C++ compilers are way more complex to implement than Ada ones.
As somebody who works on an Ada compiler, I'm not sure about that.
On some levels, Ada has a better design which simplifies compiler implementation.
On some others, the RM spec is extremely complicated - in my opinion because it was specified before it was implemented, and because of the need for safety - and very hard to implement.
See for example, dynamic access check, pool specific controlled types, anything related to elaboration, build in place for limited types, etc ..
The context dependent grammar, lookup rules, ODR, SFINAE, all the semantic interactions of template meta-programming,...
Then again that is just my perception.
This story and hommage by dwheeler https://www.dwheeler.com/essays/make-it-simple-dewar.html was one of the nicest things written on the late Robert Dewar... and on RMS !
The GNAT Front End is a large and complex piece of software and the language is very powerful thanks to all the features packed in the compiler.
On the other hand, for compliance with the standard there is a complete test suite : ACATS... It should help...
It's not like Rust has more free compilers than Ada.
https://www.adacore.com/books/safe-and-secure-software
Throw in a good article on top:
http://www.electronicdesign.com/embedded-revolution/assessin...
P.S. I thought I read SPARC.
Given that the computer industry still enjoys EULAs with disclaimers, product refunds and lawsuits due to sloppy programming or CVE exploits are still pretty rare, it is almost impossible to convince people otherwise.
One of the great outcomes of the increase in malware attacks is finally getting more buy-in for safer native languages.