This change would allow including <ciso646> to be used to check for
__GLIBCXX__ and detect whether youre using libstdc++ or not. Howard
Hinnant recommends including that header for libc++ because it has no
other effects in C++.
We could make every <cxxx> header include <bits/c++config.h> so that
any of them can be used, but I can't be bothered doing that change!
This makes it work for the one header that is recommended to be used,
but of course that doesn't help people using older versions of
libstdc++, who still need to include some other header.
Is this worth doing?
commit 0ac33b5beb231efc94ce4f0288fad36047f0325e
Author: Jonathan Wakely <jwak...@redhat.com>
Date: Thu Sep 3 11:45:29 2015 +0100
Make <ciso646> define libstdc++ version macros.
PR libstdc++/65473
* include/c/ciso646: Include <bits/c++config.h> and improve comment.
* include/c_global/ciso646: Likewise.
* include/c_std/ciso646: Likewise.
diff --git a/libstdc++-v3/include/c/ciso646 b/libstdc++-v3/include/c/ciso646
index 125f166..fb537f5 100644
--- a/libstdc++-v3/include/c/ciso646
+++ b/libstdc++-v3/include/c/ciso646
@@ -27,6 +27,6 @@
* in your programs, rather than any of the "*.h" implementation files.
*
* This is the C++ version of the Standard C Library header @c iso646.h,
- * and its contents are (mostly) the same as that header, but are all
- * contained in the namespace @c std.
+ * which is empty in C++.
*/
+#include <bits/c++config.h>
diff --git a/libstdc++-v3/include/c_global/ciso646 b/libstdc++-v3/include/c_global/ciso646
index 818db67..c59677a 100644
--- a/libstdc++-v3/include/c_global/ciso646
+++ b/libstdc++-v3/include/c_global/ciso646
@@ -27,7 +27,6 @@
* in your programs, rather than any of the @a *.h implementation files.
*
* This is the C++ version of the Standard C Library header @c iso646.h,
- * and its contents are (mostly) the same as that header, but are all
- * contained in the namespace @c std (except for names which are defined
- * as macros in C).
+ * which is empty in C++.
*/
+#include <bits/c++config.h>
diff --git a/libstdc++-v3/include/c_std/ciso646 b/libstdc++-v3/include/c_std/ciso646
index 08cdf24..ab44488 100644
--- a/libstdc++-v3/include/c_std/ciso646
+++ b/libstdc++-v3/include/c_std/ciso646
@@ -27,7 +27,6 @@
* in your programs, rather than any of the @a *.h implementation files.
*
* This is the C++ version of the Standard C Library header @c iso646.h,
- * and its contents are (mostly) the same as that header, but are all
- * contained in the namespace @c std (except for names which are defined
- * as macros in C).
+ * which is empty in C++.
*/
+#include <bits/c++config.h>
