c - What happens if i declared another variable with the same name in another file? -

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i have declared int x in file one , mistake declared variable of type char same name x in file two, , wait compiler or linker give me error, there no errors displayed. , when use debugger see int x converted char x , true?! , happens here?!

show modification on code:

file one

#include <stdio.h>  int x = 50;  /** declare global variable called                            x **/ int main() {     print();     printf("      global in file 1 = %d",x);  /** modification here **/     return 0; }

file two

char x;     void print(void) {      x = 100;     printf("global in file 2 = %d ",x);     return;  }

my expected results = global in file 2 = 100 global in file 1 = 50

but results : global in file 2 = 100 global in file 1 = 100

when use debugger see int x converted char x , true?! , happens here?

you're in troublesome territory here. technically program causes undefined behaviour. char x tentative definition, since doesn't have initializer. means linker unifies int x in other file @ link time. it's bit weird looking, since 2 declarations have different types, appears have linked in case. anyway, have 1 x, , luck making work way you're seeing (and little-endian architecture, probably).

if want 2 variables independent, make them static, , they'll restricted scope of respective translation units.


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