Example code showing this weirdness?
If something like this happened, programs would be crashing left and right.
Define "system-level code". What makes it different from, say,
bog-of-the-mill compiler code (yes, gcc compiles itself as part of its
sanity checking)?
If the related segments show code that is somehow wrong, by all means
report it /with your detailed analysis/ to the compiler people. Just a
warning, gcc is pretty smart in what it does, its code is often surprising
to the unwashed. Also, the C standard is subtle, the error might be in a
unwarranted assumption in the source code.
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