On 22/06/15 16:10 +0100, Jonathan Wakely wrote:
On 20/06/15 12:59 +0100, Jonathan Wakely wrote:
On 20/06/15 12:03 +0200, François Dumont wrote:
Hi
2 experimental tests are failing in debug mode because
__do_str_codecvt is sometimes taking address of string front() and
back() even if empty. It wasn't use so not a big issue but it still
seems better to avoid. I propose to rather use string begin() to get
buffer address.
But derefencing begin() is still undefined for an empty string.
Shouldn't that fail for debug mode too? Why change one form of
undefined behaviour that we diagnose to another form that we don't
diagnose?
It would be better if that function didn't do any work when the input
range is empty:
--- a/libstdc++-v3/include/bits/locale_conv.h
+++ b/libstdc++-v3/include/bits/locale_conv.h
@@ -58,6 +58,12 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
_OutStr& __outstr, const _Codecvt& __cvt, _State& __state,
size_t& __count, _Fn __fn)
{
+ if (__first == __last)
+ {
+ __outstr.clear();
+ return true;
+ }
+
size_t __outchars = 0;
auto __next = __first;
const auto __maxlen = __cvt.max_length() + 1;
This makes that change, and also moves wstring_convert into the
ABI-tagged __cxx11 namespace, and fixes a copy&paste error in the
exception thrown from wbuffer_convert.
This is the equivalent patch for the branch.
Tested powerpc64le-linux, committed to gcc-5-branch.
commit ab6011c5ffbd16f7f3f509f6e9fec6dc9f7daf36
Author: Jonathan Wakely <jwak...@redhat.com>
Date: Wed Jul 1 15:41:33 2015 +0100
* include/bits/locale_conv.h (wstring_convert): Use __cxx11 inline
namespace in new ABI.
(wstring_convert::_M_conv): Handle empty range.
diff --git a/libstdc++-v3/include/bits/locale_conv.h b/libstdc++-v3/include/bits/locale_conv.h
index 9be2866..de49dd5 100644
--- a/libstdc++-v3/include/bits/locale_conv.h
+++ b/libstdc++-v3/include/bits/locale_conv.h
@@ -51,6 +51,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
* @{
*/
+_GLIBCXX_BEGIN_NAMESPACE_CXX11
/// String conversions
template<typename _Codecvt, typename _Elem = wchar_t,
typename _Wide_alloc = allocator<_Elem>,
@@ -192,10 +193,17 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
_M_conv(const _InChar* __first, const _InChar* __last,
const _OutStr* __err, _MemFn __memfn)
{
+ auto __outstr = __err ? _OutStr(__err->get_allocator()) : _OutStr();
+
+ if (__first == __last)
+ {
+ _M_count = 0;
+ return __outstr;
+ }
+
if (!_M_with_cvtstate)
_M_state = state_type();
- auto __outstr = __err ? _OutStr(__err->get_allocator()) : _OutStr();
size_t __outchars = 0;
auto __next = __first;
const auto __maxlen = _M_cvt->max_length() + 1;
@@ -239,6 +247,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
bool _M_with_cvtstate = false;
bool _M_with_strings = false;
};
+_GLIBCXX_END_NAMESPACE_CXX11
/// Buffer conversions
template<typename _Codecvt, typename _Elem = wchar_t,
@@ -264,7 +273,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
: _M_buf(__bytebuf), _M_cvt(__pcvt), _M_state(__state)
{
if (!_M_cvt)
- __throw_logic_error("wstring_convert");
+ __throw_logic_error("wbuffer_convert");
_M_always_noconv = _M_cvt->always_noconv();
