[jghn]

GNAT has existed since at least the mid-90s, and in that time period plenty of companies used non-OSS compilers.

In that era, the largest blocker for Ada was it ws viewed as having a lot of overhead for things that weren't generally seen as useful (safety guarantees). The reputation was it only mattered if you were working on military stuff, etc.

[adrian_b]

True, but at that time it was already too late. C/C++ had won.

Moreover, for a very long time GNAT had been quite difficult to build, configure and coexist with other gcc-based compilers, far more difficult than building and configuring the tool chain for any other programming language. (i.e. you could fail to get a working environment, without any easy way to discover what went wrong, which never happened with any other programming language supported by gcc)

I have no idea which was the reason for this, because whichever was the reason it had nothing to do with any intrinsic property of the language.

I do not remember when it has finally become easy to use Ada with gcc, but this might have happened only a decade ago, or even more recently.

[budman1]

the gnat people needed to make a living. there were several impediments to widespread use of gnat, like the runtime license.

not that it was their responsibility to provide a free compiler to the masses.