I was student between 1990 and 1993 and Ada was the main language. Compilation speed was not an issue. I remember that Eiffel was very slow to compile, but not Ada. Between 1994 and 1999, I have worked with Ada on Vax machines. The full recompilation took 2 hours because the machine was slow, not because of the language. Other languages were similarly slow (pascal, C). C was slow because of the lack of precompiled headers (many headers had to be parsed many times). With Ada (alsys ada), there were "libraries" that were black boxes directories containing object code and already parsed package specifications. Between 1999 and 2002, I have handled projects in Ada, C++ and Java. C++ was slightly slower than Ada (slow link). Java was a lots faster. Nowadays, Ada compilation is faster than C++.