c++ - Void pointer without type casting -

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int main { void* i; printf("%d",i); return 0; }

output : (garbage value) how void pointer determines data type without typecasting??

compilers not bother types of arguments passed function printf.

the function declared following way

int printf(const char * restrict format, ...);

as see there first parameter has explicitly specified type. in general case compilers unable check whether other arguments valid.

when function executed parses first parameter searching format specifies , according these format specifiers tries interpretate following arguments.

in example format string has format specifier %d

printf("%d",i);

so function interpretates value of of type int. take account (c standard)

if argument not correct type corresponding conversion specification, behavior undefined.

among other things did not initialize variable i.


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