embedded libraries for PDP-11, was Re: [HECnet] DECUS RSX C compiler

On 10/22/2012 05:35 PM, Paul_Koning at Dell.com wrote: The main barrier to a bare metal binary, or for that matter a not so bare metal one, is the supporting libraries. I did a *really* crude hack job on newlib to give me just enough bare metal support that I could run the GCC test suite under SIMH. But that certainly isn't enough for real bare metal. A pdp11 port of newlib would be a nice project. I tried... But it is too big. I think I got a fatty library because I selected the floating point support... I tried to use sprintf() and it didn't even fit into the PDP address space :(. The printf() family is GIGANTIC. In newlib there are non-FP-enabled versions of those functions; iprintf(), siprintf(), etc. They are much, much smaller than their floating-point counterparts. I suggest you try again with that and see where things land. I'm using them on ARM7 with great results. Granted that's got a much larger address space, but my resultant binaries and stack utilization are still pretty small. The 2.11BSD lib looks leaner, and I am using it in my pet OS project (I pick the pieces I need "on the run", I have not done a complete port... yet). If the above suggestion doesn't get you anywhere, perhaps avrlibc could be hacked into a PDP-11 library. All of the hardware support will have to be ripped out of course, but there are nice tight implementations of generic library functions in there. Nice idea. Or the libc from DECUS C? Hmm yes. Will there be compiler compatibility issues there? (like with anything done in assembler, asm/C interface etc?) -Dave -- Dave McGuire, AK4HZ New Kensington, PA