Re:On the history and justification of the C programming lan...
by nickpsecurity on Thursday August 18, 2016 @06:38PM
(#12316807)
PL/I, PL/S variants, macro assembly (eg HLASM), assembly, and microcode that I can tell. PL/S was an interesting language that was high-level, not GC'd, and gave programmers control over how each function compiled. Pretty powerful for 1968. See BSL specification PDF in references section.
https://en.wikipedia.org/wiki/IBM_PL/S