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Re: RFA: Add libstdc++-v3 support for avr 4/7: fix locale_facets_nonio overloading on struct tm using template
- From: Jonathan Wakely <jwakely at redhat dot com>
- To: Joern Rennecke <joern dot rennecke at embecosm dot com>
- Cc: GCC Patches <gcc-patches at gcc dot gnu dot org>, Denis Chertykov <chertykov at gmail dot com>, Paolo Carlini <paolo dot carlini at oracle dot com>, Ulrich Drepper <drepper at gmail dot com>, Benjamin De Kosnik <bkoz at gnu dot org>
- Date: Tue, 21 Oct 2014 17:29:18 +0100
- Subject: Re: RFA: Add libstdc++-v3 support for avr 4/7: fix locale_facets_nonio overloading on struct tm using template
- Authentication-results: sourceware.org; auth=none
- References: <CAMqJFCpAKiGDusCxCrh5=Co-=6TFUw91v-22BrRLCYgFexN=cw at mail dot gmail dot com>
On 21/10/14 16:53 +0100, Joern Rennecke wrote:
libstdc++-v3:
2013-06-14 Joern Rennecke <joern.rennecke@embecosm.com>
* include/bits/locale_facets_nonio.h (__tm_small_int): typedef/define.
(_M_extract_num): Templatize base type of __member argument.
(_M_extract_name): Change type of __member argument to __tm_small_int&.
* include/bits/locale_facets_nonio.tcc (_M_extract_via_format) <Z>:
Change type of __tmp to __tm_small_int.
(_M_extract_num): Templatize base type of __member argument.
(_M_extract_name): Change type of __member argument to __tm_small_int&.
Index: include/bits/locale_facets_nonio.h
===================================================================
--- include/bits/locale_facets_nonio.h (revision 216243)
+++ include/bits/locale_facets_nonio.h (working copy)
@@ -42,6 +42,15 @@ namespace std _GLIBCXX_VISIBILITY(defaul
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
+#ifdef __AVR__
+/* The struct tm defined in avr-libc/include/time.h uses int8_t for a number
+ of fields. To allow overload resolution to succeed, we need to adjust
+ some data structures and functions to match. */
+typedef typeof (((tm*)0)->tm_sec) __tm_small_int;
I think this should probably use __typeof__ to work with
-Wpedantic-errors
+#else /* For 100% mangling compatibility, use int directly. */
+#define __tm_small_int int
+#endif
I'd prefer to always use a typedef, which can be a private member of
std::time_get, instead of defining a macro (even a macro using a
reserved name).
/**
* @brief Time format ordering data.
* @ingroup locales
@@ -654,14 +663,16 @@ namespace std _GLIBCXX_VISIBILITY(defaul
ios_base::iostate& __err, tm* __tm) const;
// Extract numeric component of length __len.
+ template <typename _Member_t>
iter_type
- _M_extract_num(iter_type __beg, iter_type __end, int& __member,
+ _M_extract_num(iter_type __beg, iter_type __end, _Member_t& __member,
int __min, int __max, size_t __len,
ios_base& __io, ios_base::iostate& __err) const;
I think this function is exported from the library, so turning it into
a template would be an ABI change.
// Extract any unique array of string literals in a const _CharT* array.
iter_type
- _M_extract_name(iter_type __beg, iter_type __end, int& __member,
+ _M_extract_name(iter_type __beg, iter_type __end,
+ __tm_small_int& __member,
const _CharT** __names, size_t __indexlen,
ios_base& __io, ios_base::iostate& __err) const;
This part should be OK, since it only affects AVR.