cmd/pdc requires readline but readline can't be found

[majenkotech]

make[3]: Entering directory '/home/matt/git/retrobsd/src/cmd/pdc'
byacc -d  pdc.y
byacc: 20 shift/reduce conflicts, 23 reduce/reduce conflicts.
/usr/bin/clang -target mipsel -mcpu=mips32r2 -mabi=o32 -msoft-float -fomit-frame-pointer -finline-hint-functions -I/home/matt/git/retrobsd/include -Wno-builtin-requires-header -Wno-deprecated-non-prototype -Werror   -Os -nostdinc -Werror -Wall -Os -DGCC_COMPAT -DHAVE_CPP_VARARG_MACRO_GCC -DHAVE_READLINE -c -o pdc.o y.tab.c
pdc.y:26:10: fatal error: 'readline/readline.h' file not found
   26 | #include <readline/readline.h>
      |          ^~~~~~~~~~~~~~~~~~~~~
1 error generated.

System: Arch Linux
Clang version: 19.1.7

Readline exists but is either not yet compiled or is not being pointed to correctly.

[majenkotech]

Running enough parallel jobs when compiling repeatedly to install as much as can be installed, then manually running make install on libreadline allows pdc to compile.

[sergev]

It compiles correctly when single threaded (make -j1). There are some issues in Makefile regarding dependencies, for parallel jobs.

[sergev]

Include files were not installed properly. I believe I fixed this issue in d57aaf6 .