I supped this morning.  Doing "make clean; make obj; make depend; make" in
/usr/src/bin/sh, I get:

     gcc -pipe -O42 -g -DSHELL -I. -I/usr/src/bin/sh   -static /usr/src/bin/sh/mkinit.c -o mkinit 
     ./mkinit 'gcc -pipe -O42 -c -g -DSHELL -I. -I/usr/src/bin/sh  init.c' mkinit builtins.c /usr/src/bin/sh/cd.c /usr/src/bin/sh/dirent.c /usr/src/bin/sh/bltin/echo.c /usr/src/bin/sh/error.c /usr/src/bin/sh/eval.c /usr/src/bin/sh/exec.c /usr/src/bin/sh/expand.c /usr/src/bin/sh/input.c /usr/src/bin/sh/jobs.c /usr/src/bin/sh/mail.c /usr/src/bin/sh/main.c /usr/src/bin/sh/memalloc.c /usr/src/bin/sh/miscbltin.c /usr/src/bin/sh/mystring.c nodes.c /usr/src/bin/sh/options.c /usr/src/bin/sh/parser.c /usr/src/bin/sh/redir.c /usr/src/bin/sh/show.c syntax.c /usr/src/bin/sh/trap.c /usr/src/bin/sh/output.c /usr/src/bin/sh/var.c
     gcc -pipe -O42 -c -g -DSHELL -I. -I/usr/src/bin/sh  init.c
     init.c:75: parse error before `:'
     init.c:88: parse error before `:'
     *** Error code 1 (continuing)

init.c has some utter bogosity on those lines:

ll. 73-76
     extern short backgndpid;	/* pid of last background process */
     extern int jobctl;
     ;tm_min:1,32,32;\
     extern int tokpushback;		/* last token pushed back */

ll. 83-88
     extern char sigmode[NSIG];	/* current value of signal */

     extern void shprocvar();
     ;ovu:41=s2ovu_magic:11,0,8;\

If I weren't so scared to think about it, I'd say that looks like pieces of
dbx stabs format.  Nah, couldn't be.

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