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digitalmars.D - How can I use ldc2 and link to full runtime on arm with no OS

reply Dan Walmsley <dan walms.co.uk> writes:
I'm starting to make attempts to find out what is needed to make 
D finally work on low level embedded targets. I have been using 
LDC2, i compile each .d file to and .o file and link using 
arm-none-eabi-gcc. I have a demo available here: 
Www.github.com/vitalelement/stm32dblinky includes a linked script.

I was originally trying to have a minimal run time approach but 
having read a lot here I don't buy the argument that these 
targets cant run with GC. So id like to now link to the full run 
time if possible and try out the GC.

However there doesn't seem to be any guide on how to do this?

I need to know, how does the run time know which area of ram to 
use for heap? In c/c++ usually we use linked script to provide an 
area of ram for this.

How do I link in the run time and gc, etc?

Many thanks

Dan
Jun 20
next sibling parent reply kinke <noone nowhere.com> writes:
On Tuesday, 20 June 2017 at 17:52:59 UTC, Dan Walmsley wrote:
 How do I link in the run time and gc, etc?
In your case, you firstly need to cross-compile druntime to your target. This means compiling most files in the src subdirectory of LDC's druntime [1], excluding obvious ones like src\test_runner.d, src\core\sys, src\core\stdcpp etc. There are also a bunch of C and assembly files which need to be cross-compiled with a matching gcc. You'll need to do this manually via something along these lines: cross-gcc -c <.c files and .asm/S files> ldc2 -mtriple=... -lib -betterC -release -boundscheck=off <.o files generated above> <list of D source modules> -of=libdruntime.a Then try linking your minimal code against that druntime (and static C libs, as druntime is built on top of the C runtime, see [2]). Depending on what features you make use of in your code, you'll need to patch linked-in druntime modules to remove the OS dependencies and possibly reduce the C runtime dependencies as well. [1] https://github.com/ldc-developers/druntime. [2] http://forum.dlang.org/thread/mojmxbjwtfmioevuoggb forum.dlang.org
Jun 20
parent reply Dan Walmsley <dan walms.co.uk> writes:
On Tuesday, 20 June 2017 at 19:44:46 UTC, kinke wrote:
 On Tuesday, 20 June 2017 at 17:52:59 UTC, Dan Walmsley wrote:
 How do I link in the run time and gc, etc?
In your case, you firstly need to cross-compile druntime to your target. This means compiling most files in the src subdirectory of LDC's druntime [1], excluding obvious ones like src\test_runner.d, src\core\sys, src\core\stdcpp etc. There are also a bunch of C and assembly files which need to be cross-compiled with a matching gcc. You'll need to do this manually via something along these lines: cross-gcc -c <.c files and .asm/S files> ldc2 -mtriple=... -lib -betterC -release -boundscheck=off <.o files generated above> <list of D source modules> -of=libdruntime.a Then try linking your minimal code against that druntime (and static C libs, as druntime is built on top of the C runtime, see [2]). Depending on what features you make use of in your code, you'll need to patch linked-in druntime modules to remove the OS dependencies and possibly reduce the C runtime dependencies as well. [1] https://github.com/ldc-developers/druntime. [2] http://forum.dlang.org/thread/mojmxbjwtfmioevuoggb forum.dlang.org
when trying to compile I'm getting lots of errors like this one: C:\dev\repos\druntime\src\gc\impl\manual\gc.d(28): Error: module config is in file 'gc\config.d' which cannot be read import path[0] = C:\Users\danw\AvalonStudio\AppData\Repos\AvalonStudio.Toolchains.LDC.win-x64.4.0.0-build2-alpha\content\bin\..\import\ldc import path[1] = C:\Users\danw\AvalonStudio\AppData\Repos\AvalonStudio.Toolchains.LDC.win-x64.4.0.0-build2-alpha\content\bin\..\import Build Failed any ideas what could be the cause?
Jun 21
next sibling parent Dan Walmsley <dan walms.co.uk> writes:
On Wednesday, 21 June 2017 at 14:53:04 UTC, Dan Walmsley wrote:
 On Tuesday, 20 June 2017 at 19:44:46 UTC, kinke wrote:
 [...]
when trying to compile I'm getting lots of errors like this one: C:\dev\repos\druntime\src\gc\impl\manual\gc.d(28): Error: module config is in file 'gc\config.d' which cannot be read import path[0] = C:\Users\danw\AvalonStudio\AppData\Repos\AvalonStudio.Toolchains.LDC.win-x64.4.0.0-build2-alpha\content\bin\..\import\ldc import path[1] = C:\Users\danw\AvalonStudio\AppData\Repos\AvalonStudio.Toolchains.LDC.win-x64.4.0.0-build2-alpha\content\bin\..\import Build Failed any ideas what could be the cause?
and also: LLVM ERROR: unsupported relocation on symbol [CC 9/164] [druntime] convert.d Build Failed LLVM ERROR: unsupported relocation on symbol after changing flags to: -c -O0 -lib -betterC -release -boundscheck=off -march=thumb -mcpu=cortex-m4 -mtriple=thumb-none-linux-eabi
Jun 21
prev sibling parent reply David Nadlinger <code klickverbot.at> writes:
On Wednesday, 21 June 2017 at 14:53:04 UTC, Dan Walmsley wrote:
 when trying to compile I'm getting lots of errors like this one:

 C:\dev\repos\druntime\src\gc\impl\manual\gc.d(28): Error: 
 module config is in file 'gc\config.d' which cannot be read

 import path[0] = 
 C:\Users\danw\AvalonStudio\AppData\Repos\AvalonStudio.Toolchains.LDC.win-x64.4.0.0-build2-alpha\content\bin\..\import\ldc

 import path[1] = 
 C:\Users\danw\AvalonStudio\AppData\Repos\AvalonStudio.Toolchains.LDC.win-x64.4.0.0-build2-alpha\content\bin\..\import

 Build Failed

 any ideas what could be the cause?
You are not adding druntime/src to the import path. I'd suggest you focus on other things first, though. Having D's GC on a platform with less than 1 MiB RAM is a rather sketchy proposition. — David
Jun 21
parent reply Dan Walmsley <dan walms.co.uk> writes:
On Wednesday, 21 June 2017 at 15:45:32 UTC, David Nadlinger wrote:
 On Wednesday, 21 June 2017 at 14:53:04 UTC, Dan Walmsley wrote:
 when trying to compile I'm getting lots of errors like this 
 one:

 C:\dev\repos\druntime\src\gc\impl\manual\gc.d(28): Error: 
 module config is in file 'gc\config.d' which cannot be read

 import path[0] = 
 C:\Users\danw\AvalonStudio\AppData\Repos\AvalonStudio.Toolchains.LDC.win-x64.4.0.0-build2-alpha\content\bin\..\import\ldc

 import path[1] = 
 C:\Users\danw\AvalonStudio\AppData\Repos\AvalonStudio.Toolchains.LDC.win-x64.4.0.0-build2-alpha\content\bin\..\import

 Build Failed

 any ideas what could be the cause?
You are not adding druntime/src to the import path. I'd suggest you focus on other things first, though. Having D's GC on a platform with less than 1 MiB RAM is a rather sketchy proposition. — David
My idea is to build the whole thing, see what the code size and performance is, and then one by one reduce things down as needed. Starting from nothing so far has been a bit of a none starter!
Jun 21
parent reply David Nadlinger <code klickverbot.at> writes:
On Wednesday, 21 June 2017 at 16:10:41 UTC, Dan Walmsley wrote:
 My idea is to build the whole thing, see what the code size and 
 performance is, and then one by one reduce things down as 
 needed.

 Starting from nothing so far has been a bit of a none starter!
This way, you'll end up having to port all of druntime to your target, though, only to then throw away considerable amounts of work that went into the parts you don't want to use. I don't think the notion of implementing a feature being easier than understanding how to rip it out is very realistic. — David
Jun 21
parent Mike <none none.com> writes:
On Wednesday, 21 June 2017 at 22:11:04 UTC, David Nadlinger wrote:

 This way, you'll end up having to port all of druntime to your 
 target, though, only to then throw away considerable amounts of 
 work that went into the parts you don't want to use.
You are correct, but if you omit certain parts of the runtime, you end up with things like these: https://github.com/ldc-developers/ldc/issues/2174 https://github.com/ldc-developers/ldc/issues/552 https://github.com/ldc-developers/ldc/issues/781 The compiler and druntime are too tightly-coupled to make pay-as-you-go D development practical. Some support to remedy that would be most welcome. Mike
Jun 21
prev sibling parent David Nadlinger <code klickverbot.at> writes:
On Tuesday, 20 June 2017 at 17:52:59 UTC, Dan Walmsley wrote:
 I need to know, how does the run time know which area of ram to 
 use for heap?
It uses C's malloc/calloc(). — David
Jun 20