This problem occurs in both mode c89 and c99.
I will try to describe it with a simple example.
----- code.c ------------------------------
#include <stdio.h>
int main(void)
{
extern int a;
printf("a: %d\n", a);
int a = 20; /* internal compiler error */
return 0;
}
-----------------------------------------
If you compile this code, you'll get follwing error message.
$ gcc -Wall -std=c89 code.c
code.c: In function `main':
code.c:7: internal compiler error: in make_decl_rtl, at varasm.c:752
Inside a block scope, the codes are executed sequently.
So I think, when there is a variable declaration with 'extern', that the
compiler should either let occur an error of double variable-declaration or show
warning only and just give the local variable priority.
Thank you for reading.
--
Summary: Error on reference of 'extern' variable in block scope.
Product: gcc
Version: 3.4.3
Status: UNCONFIRMED
Severity: normal
Priority: P2
Component: c
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: sorie at sorie dot net
CC: gcc-bugs at gcc dot gnu dot org
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=18935
