Can code that is valid in both C and C++ produce different behavior when compiled in each language?

C and C++ have many differences, and not all valid C code is valid C++ code.

(By "valid" I mean standard code with defined behavior, i.e. not implementation-specific/undefined/etc.)

Is there any scenario in which a piece of code valid in both C and C++ would produce different behavior when compiled with a standard compiler in each language?

To make it a reasonable/useful comparison (I'm trying to learn something practically useful, not to try to find obvious loopholes in the question), let's assume:

• Nothing preprocessor-related (which means no hacks with #ifdef __cplusplus, pragmas, etc.)

• Anything implementation-defined is the same in both languages (e.g. numeric limits, etc.)

• We're comparing reasonably recent versions of each standard (e.g. say, C++98 and C90 or later)

If the versions matter, then please mention which versions of each produce different behavior.

The following, valid in C and C++, is going to (most likely) result in different values in i in C and C++:
int i = sizeof('a');


See Why is the size of a character sizeof('a') different in C and C++? for an explanation of the difference.

Another one from this article:
#include

int sz = 80;

int main(void)
{
struct sz { char c; };

int val = sizeof(sz); // sizeof(int) in C,
// sizeof(struct sz) in C++
printf("%d\n", val);
return 0;
}


Stack Overflow Q#12887700, score: 422