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0 pointsakdev1l1y ago0 comments

I think it is UB

Edit: actually looks like it is UB in C++ but not C

0 comments

colejohnson661y ago

Why would calling main be UB!? How is crt0 supposed to work?

tomjakubowski1y ago

crt0 generally isn't C and isn't subject to C's rules

astrange1y ago

malloc() can't be implemented in C either because it's defined as doing things (creating new memory objects) there are no lower level mechanisms in C to do.

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akdev1lOP1y ago

As the other person pointed out, anything that happens before main is strictly not covered by the C standard.

Even things like “printf” can’t be implemented purely in standard C. Even making a syscall is outside of the scope of the C standard.

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