John Parkes <jp012c6013@xxxxxxxxxxxxxxxx> writes: > Is GCC permitted to miscompile, with -fstrict-aliasing, source > which clearly flouts the assumptions of that option ? [snip] 'miscompile' is not the right word. According to the standard, the behaviour of your example has undefined behavior. So the code the gcc produces is not a 'miscompilation' no matter what it does.