I’m trying to use the NDK toolchain to build some native library I have for ARM.
I’m also using the ARMv7 NEON intrinsics in part of my code. Unfortunately I get the
following type of error in several places in my code:
internal compiler error: in write_builtin_type, at cp/mangle.c:1855
The error seems to be triggered by using the float32_t type defined in the
arm_neon.h – e.g. I get the compiler crash when using a std::vector<float32_t>.
For Android ARM the single precision floating point type is a typedef for an
internal compiler builtin type whereas for Linaro Linux for example is just a typedef
of the C/C++ float – see arm_neon.h in the case of both compilers(I can build the same
sources with the Linaro Linux toolchain without any problem).
I also found an old post in the android NDK Google group that seems to describe the same problem but unfortunately it did not present any solution:
Some old post describing the same compiler crash
Does anyone have any hint on how to overcome the above problem?
Is there any special reason a builtin compiler type is used and not the normal float as in the case of the Linaro toolchain for example?
If I replace the typedef would I cause unwanted/undefined behavior?
Does anyone know if the toolchain included in the NDK based on the CodeSourcery toolchain, because the CS one is really buggy and the code base we have breaks it in many ways(just as info so that I know I have to definitely change the toolchain)?
I’m using:
-
Android NDK version r8
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NDK toolchain gcc (GCC) 4.4.3 – stripped outside the NDK as advised in the NDK documentation
Update:
Found this other SO question that illustrates pretty much the same issue … the scary thing is that it’s from 2010.
Update 2:
Replacing the typedef is not an option as it will break completely the NEON intrinsics functionality. All the floating point intrinsics rely on builtin compiler functions which expect the __builtin_neon_sf(the typedef for float32_t) type as their parameter(s).
This is a compiler bug. I’ve opened one new issue in the Android project bug tracker.
Unfortunately to overcome it I had to rewrite the whole portion of code which was causing it.