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0 pointsWalterBright1y ago0 comments

> A good example is format strings in C

The D programming language allows direct use of C printf. However, D checks the arguments against the format specifiers in the format string to make it memory safe.

The constant stream of bugs due to format/arguments is now history.

There is no reason why C and C++ compilers cannot do this, too.

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notepad0x901y ago

for static specifiers, I can see that. but for dynamically constructed format specifiers, especially where arrays to pointers/vargs are in use, is it possible to have a mitigation for that?

this pseudo-code as an example:

snprintf(fmt,userinputstring,args); printf(fmt,somearray);

WalterBrightOP1y ago

Your suspicion is correct, the checks only work when the format string is a literal.

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