pdp11-cc

The compiler driver: runs cpp → c0 → c1 [→ c2 with -O] → as → ld to turn C into a runnable PDP-11 a.out. This is the authentic 2.9BSD cc, extended with universe selection.

pdp11-cc [--universe=U | -u U] [-c|-S|-E|-P] [-O] [-o out] [-v]
         [-D -I -U -C options] [-V overlay mode] file.c ... [-lx ...]

• One driver, every era. --universe (or $PDP11_UNIVERSE, default bsd29) is validated against src/common/universes.tsv and exported to the child passes, so cpp reads include/<universe>/ and ld links lib/<universe>/{crt0.o, libc.a} without flags of their own.
• No compiled-in paths. The passes are resolved relative to the driver's own location: a <prefix>-cc runs its sibling <prefix>-cpp, <prefix>-c0, ... — the prefix is everything through the last - in argv[0], so the whole toolchain relocates as a unit.
• The overlay pipeline is built in. -V compiles for text overlays (-DC_OVERLAY, as -V ovas mode, -lovc), matching 2.9's MENLO_OVLY toolchain; there is no separate ovcc/ovas/ovld.
• Host-porting fixes over the vintage source: $TMPDIR honoured for pass temporaries, and the -E/-P null-temp crash fixed.

cc accepts K&R / pre-1977 C (the C the 2.9BSD compiler itself is written in): old-style definitions, implicit int, and so on.

Documentation

• Design — the driver: pass sequencing, universe selection, and temp-file management.
• User guide — the options, universe selection, and examples.
• docs/porting.md — the LP64 porting guide inherited from the source project.

Build and test

make          # (repo root or this dir) builds ../../bin/pdp11-cc
make check    # covered by the end-to-end suite (tests/cc/*.sh at the
              # repo root): compile/link/run under apsim, both
              # universes, plain and -O