https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92688
Bug ID: 92688
Summary: including <regex> introduce the name index to global
namespace scope
Product: gcc
Version: 10.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: libstdc++
Assignee: unassigned at gcc dot gnu.org
Reporter: boostcpp at gmail dot com
Target Milestone: ---
This code introduce regression after GCC 4.9 and onward.
#include <regex>
template < typename T >
struct index { }
int main() { }
Also, this code fails to compile even at GCC 4.4.7(I don't have an easy test
environment of GCC older than this version)
#include <cstring>
int index ;
int main(){}
The reason is <regex> include <cstring>, which include <string.h> which has a
function name index on global namespace scope. The index function was
originally came from <strings.h>. For some reason, its name is declared on
default in <string.h>
<strings.h> and its index function is not part of the C++ standard nor C
standard. it has been deprecated long ago. GCC without GNU extention(like with
option -std=c++XX) shall not pollute the global namespace scope with the
non-standard conforming library name that is so generic like "index" if it only
include the standard library header files.
