C++ standard quote:
3.3.2, paragraph 4:
Names declared in the for-init-statement, and in the condition of if, while,
for, and switch statements are local to the if, while, for, or switch statement
(including the controlled statement), and shall not be re-declared in a
subsequent condition of that statement nor in the outermost block (or, for the
if statement, any of the outermost blocks) of the controlled statement; see 6.4.
However g++/gcc happily compiles:
#include
int main(void)
{
for(int i=2;i<4;i++)
{
int j = i;
int i;
i = 555;
printf("%d %d\n", i, j);
}
return 0;
}
and allows re-declaration of i.
No warning/remark/error is given.
This should trigger an error.
Maybe it could be a gcc extension to the standard(s), but then it should
be clearly marked as such.
The C99 standard is a bit less clear about this but I believe this should also
apply to C99.
Command lines used:
gxx -W -Wall -ansi -pedantic main.cpp
gcc -W -Wall -std=c99 -pedantic main.c
--
Summary: C++/C99 standard violation in for loop
Product: gcc
Version: 4.0.0
Status: UNCONFIRMED
Severity: normal
Priority: P2
Component: c++
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: ahelm at gmx dot net
CC: gcc-bugs at gcc dot gnu dot org
GCC host triplet: DJGPP
GCC target triplet: MS-DOS
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21837