#15636: Document ABI conventions
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Reporter: X512 | Owner: nobody
Type: task | Status: new
Priority: normal | Milestone: Unscheduled
Component: System | Version: R1/Development
Resolution: | Keywords:
Blocked By: | Blocking:
Has a Patch: 0 | Platform: All
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Description changed by X512:
Old description:
ABI conventions used by Haiku for each architecture (x86 gcc2, x86 gcc4+,
x86_64) should be documented in some way (in web site, HaikuBook etc.).
At least following topics should be documented:
* Preserved registers, including SIMD registers etc.
* FPU state.
* Passing arguments to function and return value.
* Stack alignment including alignment origin.
* Exception handling and stack unwinding.
* Executable format.
If Haiku use some existing ABI, it should be referenced in documentation
with Haiku specific changes, if any.
I tried to port some non C/C++ compiler (target ABI: x86 gcc4+) and make
Haiku API bindings and experience various problems such as:
* Structs passed by value (such as `pattern`) are stored on stack as is,
but classes such as `BPoint` are passed by pointer.
* `StrokeLine(BPoint, BPoint, pattern)` is not working if stack is not
aligned.
