> On 4 Dec 2018, at 14:53, Clem Cole wrote: > On Tue, Dec 4, 2018 at 9:43 AM Noel Chiappa > wrote: > Which brings up an interesting query - I wonder when/what the last compiler written in assembler was? > Excellent question -- IBM's Fortran-H maybe? circa mid 1970's would be my guess. > ᐧ The Fortran H compiler was mostly written in Fortran: 27,415 lines of Fortran and 16,721 lines of assembler according to slide 12 of [1]. There were some language extensions (structures and pointers) to support this, enabled by the secret compiler option XL. They are described in Appendix J of the Program Logic Manual for the compiler [2]. The early-1980s Fortran 77 compiler for the GEC 4090 was written in Babbage, a thin PL/360-like veneer over the raw 4090 instruction set. [1] http://booksite.elsevier.com/9780120884780/Graduate_Lecture_Slides/Core_Lectures/02FortranH.ppt [2] http://www.bitsavers.org/pdf/ibm/360/fortran/Y28-6642-3_FortH_PLM_Nov68.pdf