[En-Nut-Discussion] stm32_can.c fails to build

[Harald Kipp]

I got the following problem when trying to build Nut/OS for STM32:

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Target : stm32_can-cm3-gcc-bld
Command: SET PATH=e:\ethernut\nut-trunk\nut\tools\win32;%ProgramFiles(x86)%\yagarto\bin;e:\apps\bin;%SystemRoot%\system32;%SystemRoot%;%SystemRoot%\System32\Wbem;&make clean all install
Error  : 2
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"  [CC] ../.././nut/arch/cm3/dev/stm/stm32_can.c"
../.././nut/arch/cm3/dev/stm/stm32_can.c: In function 'StmCanSendMsg':
../.././nut/arch/cm3/dev/stm/stm32_can.c:867:5: error: dereferencing type-punned pointer will break strict-aliasing rules [-Werror=strict-aliasing]
../.././nut/arch/cm3/dev/stm/stm32_can.c: In function 'CanInput':
../.././nut/arch/cm3/dev/stm/stm32_can.c:941:5: error: dereferencing type-punned pointer will break strict-aliasing rules [-Werror=strict-aliasing]
cc1.exe: all warnings being treated as errors

make[1]: *** [cm3/dev/stm/stm32_can.o] Error 1
make[1]: Leaving directory `E:/ethernut/ethernut-5.0.5/stm32_can-cm3-gcc-bld/arch'
make: *** [all] Error 2