Redeclaration of global variable vs local variable

Question

When I compile the code below

#include

int main()
{
  int a;
  int a = 10;
  printf(\"a is %d \\n\",a);
  return 0;
}

I get

Answer 1

The other reason I could think of is that un-initialized global variables are stored in the BSS (Block Structured Segment) where are the global variables that are initialized are stored in Data Segment.

I am guessing that there is some kind of a name space resolution and when there is a conflict the variable in the Data segment overrides the one in the Block Structured Segment.

if you were to declare

int a =5 int a = 10

in the global scope (both in the data segment) there would be conflict as expected.