Building with -std=c++0x causes __STRICT_ANSI__ to be defined. The new C++
headers expect the system C headers (ctype.h, stdio.h, etc.,) to declare
certain functions (isblank(), snprintf(), etc.) that are part of C++0x. The
system C headers that are part of cygwin aren't privy to this. The result is
that simple programs like the following to not compile with -std=c++0x on a
stock cygwin install.
#include <iostream>
int main() {}
The error is:
In file included from
/usr/local/gcc-4.3-20071030/lib/gcc/i686-pc-cygwin/4.3.0/../../../../include/c
++/4.3.0/cctype:98,
from
/usr/local/gcc-4.3-20071030/lib/gcc/i686-pc-cygwin/4.3.0/../../../../include/c
++/4.3.0/bits/localefwd.h:49,
from
/usr/local/gcc-4.3-20071030/lib/gcc/i686-pc-cygwin/4.3.0/../../../../include/c
++/4.3.0/ios:47,
from
/usr/local/gcc-4.3-20071030/lib/gcc/i686-pc-cygwin/4.3.0/../../../../include/c
++/4.3.0/ostream:45,
from
/usr/local/gcc-4.3-20071030/lib/gcc/i686-pc-cygwin/4.3.0/../../../../include/c
++/4.3.0/iostream:45,
from main.cpp:1:
/usr/local/gcc-4.3-20071030/lib/gcc/i686-pc-cygwin/4.3.0/../../../../include/c++/4.3.0/tr1_impl/ccty
pe:43: error: '::isblank' has not been declared
For another example, the following program also does not compile on cygwin with
-std=c++0x:
#include <cstdio>
int main()
{
char buf[50];
snprintf(buf, 50, "hello");
}
main.cpp: In function 'int main()':
main.cpp:6: error: 'snprintf' was not declared in this scope
This is with a stock g++ built on cygwin from latest source from svn,
configured with "--prefix=/usr/local/g++-4.3 --enable-languages=c,c++".
--
Summary: -std=c++0x causes undeclared symbols errors on cygwin
Product: gcc
Version: 4.3.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: eric dot niebler at gmail dot com
GCC host triplet: cygwin
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34032
