[avr-chat] Strange struct problem

[Daniel O'Connor]

Hi,
I am getting this odd problem with structs. If the size of the struct 
is larger than 4 bytes I can't access it.. It's most peculiar.

I have a test case (attached).

Build it with..
avr-gcc -O2 -fno-strict-aliasing -pipe  -g -Wall -Wunreachable-code 
-DF_CPU=16000000 -mmcu=atmega32 -Wa,-adhlmsn=testcase.lst -c testcase.c -o 
testcase.o
avr-gcc -O2 -fno-strict-aliasing -pipe  -g -Wall -Wunreachable-code 
-DF_CPU=16000000 -mmcu=atmega32  -Wl,-Map=testcase.map,--cref  -g testcase.o -o 
testcase.elf 
avr-objcopy -j .text -O ihex testcase.elf testcase.hex
avr-objdump -S testcase.elf > testcase.dmp

If BREAKME is defined all the struct accesses return 255 instead of what
they should be (I think :)

I am wondering if there is some oddity with GCC optimising for <= 4 byte
structs which unbreaks my code, but I can't see why it is broken.

Any help gratefully received!

-- 
Daniel O'Connor software and network engineer
for Genesis Software - http://www.gsoft.com.au
"The nice thing about standards is that there
are so many of them to choose from."
  -- Andrew Tanenbaum
GPG Fingerprint - 5596 B766 97C0 0E94 4347 295E E593 DC20 7B3F CE8C

testcase.c
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