libstdc++: Move new std::generate_canonical to inline namespace

This ensures that the new definition of std::generate_canonical has a
different mangled name from the old one, so that TUs compiled with GCC
16 will be sure to use the new definition, even if the linker also sees
a symbol instantiated from the old definition. We use the same _V2
inline namespace as used elsewhere (std::_V2::condition_variable,
std::_V2::__rotate, and std::chrono::_V2::system_clock), and use a macro
to add it conditionally so that it's not used for the ABI-unstable
gnu-versioned-namespace configuration.

We can simplify the 26_numerics/random/pr60037-neg.cc test to only use
one dg-error without a line number, so that it matches any of the three
relevant static_assert failures for this test: the one from _Adaptor in
<bits/random.h> and the ones from the new and old definitions of
std::generate_canonical in <bits/random.tcc>. Without this change, the
line number for the dg-error matching the <bits/random.tcc> error
depends on the _GLIBCXX_USE_OLD_GENERATE_CANONICAL macro, which is
awkward to depend on in the test (because DejaGnu sees all dg-error
directives, it doesn't care if they're guarded by #ifdef preprocessor
checks).

libstdc++-v3/ChangeLog:

	* include/bits/random.h [!_GLIBCXX_USE_OLD_GENERATE_CANONICAL]
	(generate_canonical): Use inline namespace _V2.
	* include/bits/random.tcc [!_GLIBCXX_USE_OLD_GENERATE_CANONICAL]
	(generate_canonical): Likewise.
	* testsuite/26_numerics/random/pr60037-neg.cc: Remove lineno so
	that one dg-error matches both diagnostics.

Reviewed-by: Tomasz Kamiński <tkaminsk@redhat.com>

diff --git a/libstdc++-v3/include/bits/random.h b/libstdc++-v3/include/bits/random.h
index ebc863e84534463b5c3779e43d0c14924b8408c5..5a959ed6ebecca2d19c6f228c688013c89736e99 100644 (file)
--- a/libstdc++-v3/include/bits/random.h
+++ b/libstdc++-v3/include/bits/random.h
@@ -51,6 +51,9 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 
   // std::uniform_random_bit_generator is defined in <bits/uniform_int_dist.h>
 
+#ifndef _GLIBCXX_USE_OLD_GENERATE_CANONICAL
+_GLIBCXX_BEGIN_INLINE_ABI_NAMESPACE(_V2)
+#endif
   /**
    * @brief A function template for converting the output of a (integral)
    * uniform random number generator to a floatng point result in the range
@@ -60,6 +63,9 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
           typename _UniformRandomNumberGenerator>
     _RealType
     generate_canonical(_UniformRandomNumberGenerator& __g);
+#ifndef _GLIBCXX_USE_OLD_GENERATE_CANONICAL
+_GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
+#endif
 
   /// @cond undocumented
   // Implementation-space details.

diff --git a/libstdc++-v3/include/bits/random.tcc b/libstdc++-v3/include/bits/random.tcc
index c3b4776d35804750c84bdd047a0264c61c200ad3..e16eb9814a554ec65ad7ac490ece206385873b7b 100644 (file)
--- a/libstdc++-v3/include/bits/random.tcc
+++ b/libstdc++-v3/include/bits/random.tcc
@@ -3624,6 +3624,7 @@ namespace __detail
     constexpr bool __is_power_of_2_less_1(_Rng __range)
       { return ((__range + 1) & __range) == 0; };
 
+_GLIBCXX_BEGIN_INLINE_ABI_NAMESPACE(_V2)
   /** Produce a random floating-point value in the range [0..1)
    *
    * The result of `std::generate_canonical<RealT,digits>(urng)` is a
@@ -3700,6 +3701,7 @@ namespace __detail
            }
        }
     }
+_GLIBCXX_END_INLINE_ABI_NAMESPACE(_V2)
 
 #pragma GCC diagnostic pop
 

diff --git a/libstdc++-v3/testsuite/26_numerics/random/pr60037-neg.cc b/libstdc++-v3/testsuite/26_numerics/random/pr60037-neg.cc
index 13c4dc8724a45da2d476a75054277616d6081e02..93467eb2046a5b3786918d267695c4ab0513dbf9 100644 (file)
--- a/libstdc++-v3/testsuite/26_numerics/random/pr60037-neg.cc
+++ b/libstdc++-v3/testsuite/26_numerics/random/pr60037-neg.cc
@@ -10,7 +10,4 @@ std::__detail::_Adaptor<std::mt19937, unsigned long> aurng(urng);
 auto x = std::generate_canonical<std::size_t,
                        std::numeric_limits<std::size_t>::digits>(urng);
 
-// { dg-error "static assertion failed: template argument must be a floating point type" "" { target *-*-* } 271 }
-
-// { dg-error "static assertion failed: template argument must be a floating point type" "" { target *-*-* } 3650 }
-
+// { dg-error "static assertion failed: template argument must be a floating point type" "" { target *-*-* } 0 }