I thought I was stymied by not having any big-endian hosts where I could test code that appeared to have big-endian limitations...

turns out there's a way to do it on Intel hosts, almost transparently!

Running a MIPS emulator... the easy way...

% sudo apt-get install gcc-multilib-mips-linux-gnu gcc-mips-linux-gnu qemu-user

% cat > test.c <<EOD
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include <limits.h>
#if CHAR_BIT != 8
#error "Unsupported char size for detecting endianness"
#endif

int main (void)
{
  short int word = 0x0001;
  char *byte = (char *) &word;
  if (byte[0]) printf("little endian");
  else printf("big endian");
  return 0;
}
EOD

% mips-linux-gnu-gcc test.c -o test -static
% ./test
big endian

% cc -o itest test.c
% ./itest
little endian


PS I also installed a sparc cross-compiler:

gtoal@linux:~/mips$ sparc64-linux-gnu-gcc test.c -o stest -static
gtoal@linux:~/mips$ ./stest
big endian

gtoal@linux:~/mips$ sparc64-linux-gnu-gcc -m32 test.c -o stest -static
gtoal@linux:~/mips$ ./stest
big endian