This is the mail archive of the
gcc-patches@gcc.gnu.org
mailing list for the GCC project.
Re: [PATCH] P0935R0 Eradicating unnecessarily explicit default constructors
- From: Jonathan Wakely <jwakely at redhat dot com>
- To: libstdc++ at gcc dot gnu dot org, gcc-patches at gcc dot gnu dot org
- Date: Fri, 15 Jun 2018 17:13:22 +0100
- Subject: Re: [PATCH] P0935R0 Eradicating unnecessarily explicit default constructors
- References: <20180612191036.GA3342@redhat.com>
On 12/06/18 20:10 +0100, Jonathan Wakely wrote:
Explicit default constructors are problematic, so this change removes
them from <random> and <ext/random>, as per P0935R0.
* include/bits/random.h (linear_congruential_engine)
(mersenne_twister_engine, subtract_with_carry_engine, random_device)
I forgot to remove the default argument in the no-/dev/urandom version
of std::random_device. Fixed like so.
(Incidentally, it makes me very sad that our std::random_device is
5000 bytes even when it only needs to store a pointer, because we have
a union with mt19937 in it).
commit 8c359baec670ed7d0305d376ebf8ebb209e50a8a
Author: Jonathan Wakely <jwakely@redhat.com>
Date: Fri Jun 15 17:10:06 2018 +0100
PR libstdc++/86168 fix ambiguous default constructor
PR libstdc++/86168
* include/bits/random.h (random_device(const string&)): Remove
default argument.
diff --git a/libstdc++-v3/include/bits/random.h b/libstdc++-v3/include/bits/random.h
index 738c62fccd1..e59c8b0221d 100644
--- a/libstdc++-v3/include/bits/random.h
+++ b/libstdc++-v3/include/bits/random.h
@@ -1614,7 +1614,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
random_device() { _M_init("mt19937"); }
explicit
- random_device(const std::string& __token = "mt19937")
+ random_device(const std::string& __token)
{ _M_init_pretr1(__token); }
#endif