I'm using HEW to target code for the Renesas RX platform. I started a C++ project from scratch and, I think, set up most of the build environment correctly. I realize that my question is more of a tools question than an OS question, but I think this forum is the place where I'm likely to get the best answer.

I've reduced the compile/link errors I'm getting to two:

Phase Linker starting
C:\Code\OS\Segger_embOS\GNURX\LIB\libosLDP.a(OS_StackInfo.o): In function `OS_GetSysStackBase':
(.text+0x2): undefined reference to `ram_start'
C:\Code\OS\Segger_embOS\GNURX\LIB\libosLDP.a(OS_StackInfo.o): In function `OS_GetSysStackSize':
(.text+0xf): undefined reference to `ram_start'
Phase Linker finished

In a project targeting the RX platform, and using the GNU RX toolchain, where is ram_start defined?



I have a second project; it's the same code but targets the HEW compiler. Though I believe my build environments between the two projects are the same, there's still something wrong. When I compile my HEW project, the linker gives me:

L2310 (E) Undefined external symbol "_OS_CreateTaskEx_R" referenced in "C:\Code\MyProject_HEWRX\Debug\debugtask.obj"
L2310 (E) Undefined external symbol "_OS_CreateTaskEx_R" referenced in "C:\Code\MyProject_HEWRX\Debug\guitask.obj"

What did I fail to include in my build environment that is causing this linker error?

As a newcomer to embOS, and even to C programming in an embedded environment, I appreciate any help the community can offer.

I found that to resolve the undefined reference to ram_start, I had to go to the build menu, toolchain, Link/Library tab, Sections category, show entries for Sections, and add a .ram_start section with a _ram_start label.

I did this by comparing a C project that worked against my C++ project that wouldn't link.

I am not at all confident that I selected an appropriate start address for _ram_start. While this is, again, a tools issue more than an OS issue, if anyone has any pointers for me on how to ensure that my linker sections are configured properly for the GNU RX compiler, I'd appreciate it. Meanwhile, I'll see if I can't find any documentation on this.

I am also curious to know why libosLDP requires ram_start when linked with the GNU toolchain, but not when linked with the RX toolchain. There appears to be no definition (though I may be wrong) for ram_start in the project settings for my RX toolchain version of this project.

Any explanation would be appreciated.