Merging of string literals guaranteed by C std?

Hi group,

I have a question about string literals and the address that they point
to. Does the standard *guarantee* that two identical string literals
actually point to the same address. I.e. can we safely assert:

assert("foo" == "foo");

Or can it maybe only be asserted if the literal occurs in one
compilation unit (i.e. not across compilation units)?

My gut feeling tells me that I cannot rely on the addresses being
identical, but I cannot find it in N1124. It would make things much
easier/cooler if the standard would assert that in my situation, but I
don't want to rely on compiler behavior alone (gcc merges the string
literals into one address even with -O0).

Best regards,
Johannes


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