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From: Norman Goldstein <normvcr@telus.net>
Newsgroups: gnu.utils.bug
Subject: ld resolving different types
Date: Sat, 15 Feb 2020 16:51:14 -0800
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Xref: csiph.com gnu.utils.bug:2276

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LD version:
    GNU ld version 2.31.1-37.fc30

Platform:
    Linux 5.4.17-100.fc30.x86_64 #1 SMP     x86_64 x86_64 x86_64 GNU/Linux

Compile/Link command:
     gcc tlink.cpp tlink2.cpp -o tlink -lstdc++

The programs compiles and links without warning or error, but resolves 
/extern int foo/ with /double foo/.  The result of running the program 
is, of course, garbage:

foo= -858993459

The program contains only 1 definition for foo (the extern statement is 
a declaration), so the program is not violating the One Definition Rule.

Thank you.




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#include <iostream>
using namespace std;

extern int foo;

int main( int argc, char* argv[] )
{
  cout << "foo= " << foo << endl;

  return 0;
}// main

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double foo = 2.1;

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