Re: [PATH][_GLIBCXX_DEBUG] Fix unordered container merge

["François Dumont" <frs.dumont@gmail.com>]

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On 10/11/21 10:38 am, Jonathan Wakely wrote:
>
>
> On Wed, 10 Nov 2021 at 05:47, François Dumont <frs.dumont@gmail.com 
> <mailto:frs.dumont@gmail.com>> wrote:
>
>     On 09/11/21 5:25 pm, Jonathan Wakely wrote:
>>
>>
>>     On Mon, 8 Nov 2021 at 21:36, François Dumont
>>     <frs.dumont@gmail.com <mailto:frs.dumont@gmail.com>> wrote:
>>
>>         Yet another version this time with only 1 guard
>>         implementation. The predicate to invalidate the safe
>>         iterators has been externalized.
>>
>>         Ok to commit ?
>>
>>
>>     I like this version a lot - thanks for persisting with it.
>>
>>     OK to commit, thanks.
>>
>>
>>     As an aside ...
>>
>>     --- a/libstdc++-v3/testsuite/util/testsuite_abi.h
>>     +++ b/libstdc++-v3/testsuite/util/testsuite_abi.h
>>     @@ -24,7 +24,11 @@
>>      #include <locale>
>>      #if __cplusplus >= 201103L
>>      # include <unordered_map>
>>     +# ifdef _GLIBCXX_DEBUG
>>     +namespace unord = std::_GLIBCXX_STD_C;
>>     +# else
>>      namespace unord = std;
>>     +# endif
>>      #else
>>      # include <tr1/unordered_map>
>>      namespace unord = std::tr1;
>>
>>
>>     Several times I've been annoyed by the fact that we don't have a
>>     way to refer to std::_GLIBCXX_STD_C::vector etc. that is always
>>     valid, in normal mode and debug mode.
>>
>>     Maybe we should add:
>>
>>     namespace std { namespace _GLIBCXX_STD_C = ::std; }
>>
>>     That way we can refer to std::_GLIBCXX_STD_C::foo in normal mode,
>>     and it will mean the same thing as in debug mode. So we don't
>>     need to use #if conditions like this.
>>
>>
>     Good idea, I'll prepare it.
>
>
> Alternatively we could do this:
>
> namespace std
> {
> namespace __cxx1998 { }
> #ifdef _GLIBCXX_DEBUG
> namespace __cont = __cxx1998;
> #else
> namespace __cont = ::std::
> #endif
> }
>
> And then define this so it's always the same name:
> #define _GLIBCXX_STD_C __cont
>
> Then we can refer to std::_GLIBCXX_STD_C::vector in any context, and 
> it refers to the right thing. And we could also stop using the 
> SHOUTING macro, and just refer to std::__cont::vector instead.
>
> We could also make this work as std::__cxx1998::vector, but maybe we 
> should move away from the "1998" name, because it doesn't make much 
> sense for forward_list and unordered_map which are not in C++98.
>
Here is what I started.

I use '__normal' because when greping '__cont' in the lib it reported me 
a definition of it in boost_concept_check.h. But now that I took a 
closer look in this file I realize that it is just where you pick the 
idea of the '__cont' !

So, what do you prefer ? __cont or __normal ?

I was not considering to replace usage of _GLIBCXX_STD_C in the lib as 
long as there is no #ifdef _GLIBCXX_DEBUG. Do you prefer I do ?

François


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diff --git a/libstdc++-v3/include/bits/c++config b/libstdc++-v3/include/bits/c++config
index 4b7fa659300..becd83af4d9 100644
--- a/libstdc++-v3/include/bits/c++config
+++ b/libstdc++-v3/include/bits/c++config
@@ -245,6 +245,7 @@
     namespace __debug { }
     namespace __parallel { }
     namespace __cxx1998 { }
+    namespace __normal { }
 
     namespace __detail {
       namespace __variant { }				// C++17
@@ -384,6 +385,8 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 # endif
   }
 
+  namespace __normal = __cxx1998;
+
 _GLIBCXX_END_NAMESPACE_VERSION
 
   // Inline namespace for debug mode.
@@ -407,6 +410,11 @@ _GLIBCXX_END_NAMESPACE_VERSION
 #  warning currently using inlined namespace mode which may fail \
    without inlining due to lack of weak symbols
 # endif
+#else
+namespace std
+{
+  namespace __normal = ::std;
+}
 #endif
 
 // Macros for namespace scope. Either namespace std:: or the name
diff --git a/libstdc++-v3/testsuite/23_containers/forward_list/capacity/1.cc b/libstdc++-v3/testsuite/23_containers/forward_list/capacity/1.cc
index dc2a2be3867..399064ea074 100644
--- a/libstdc++-v3/testsuite/23_containers/forward_list/capacity/1.cc
+++ b/libstdc++-v3/testsuite/23_containers/forward_list/capacity/1.cc
@@ -35,12 +35,7 @@ test01()
   fld.resize(0);
   VERIFY(fld.empty() == true);
 
-#ifdef _GLIBCXX_DEBUG
-  using std::_GLIBCXX_STD_C::_Fwd_list_node;
-#else
-  using std::_Fwd_list_node;
-#endif
-
+  using std::__normal::_Fwd_list_node;
   std::allocator<_Fwd_list_node<double> > a;
   VERIFY( fld.max_size() == __gnu_test::max_size(a) );
 }
diff --git a/libstdc++-v3/testsuite/util/testsuite_abi.h b/libstdc++-v3/testsuite/util/testsuite_abi.h
index 4a0cf64f6fb..d0902db9193 100644
--- a/libstdc++-v3/testsuite/util/testsuite_abi.h
+++ b/libstdc++-v3/testsuite/util/testsuite_abi.h
@@ -24,11 +24,7 @@
 #include <locale>
 #if __cplusplus >= 201103L
 # include <unordered_map>
-# ifdef _GLIBCXX_DEBUG
-namespace unord = std::_GLIBCXX_STD_C;
-# else
-namespace unord = std;
-# endif
+namespace unord = std::__normal;
 #else
 # include <tr1/unordered_map>
 namespace unord = std::tr1;