re PR libstdc++/14220 ([3.5] num_put::do_put() undesired float/double behavior)

2004-07-29  Paolo Carlini  <pcarlini@suse.de>

	PR libstdc++/14220
	* include/bits/locale_facets.tcc (num_put<>::_M_insert_float):
	Don't clip the precision passed down to __convert_from_v:
	22.2.2.2.2 nowhere says so.
	* testsuite/22_locale/num_put/put/char/14220.cc: New.
	* testsuite/22_locale/num_put/put/wchar_t/14220.c: Likewise.

From-SVN: r85315

4 files changed, 118 insertions, 20 deletions

diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog
index e58e61d..4a2381a 100644
--- a/libstdc++-v3/ChangeLog
+++ b/libstdc++-v3/ChangeLog
@@ -1,5 +1,14 @@
 2004-07-29  Paolo Carlini  <pcarlini@suse.de>
 
+	PR libstdc++/14220
+	* include/bits/locale_facets.tcc (num_put<>::_M_insert_float):
+	Don't clip the precision passed down to __convert_from_v:
+	22.2.2.2.2 nowhere says so.
+	* testsuite/22_locale/num_put/put/char/14220.cc: New.
+	* testsuite/22_locale/num_put/put/wchar_t/14220.c: Likewise.
+
+2004-07-29  Paolo Carlini  <pcarlini@suse.de>
+
 	* docs/html/ext/lwg-active.html, lwg-defects.html: Import Revision 31.
 
 2004-07-29  Paolo Carlini  <pcarlini@suse.de>
diff --git a/libstdc++-v3/include/bits/locale_facets.tcc b/libstdc++-v3/include/bits/locale_facets.tcc
index b967cee..94a2cb8 100644
--- a/libstdc++-v3/include/bits/locale_facets.tcc
+++ b/libstdc++-v3/include/bits/locale_facets.tcc
@@ -1052,29 +1052,20 @@ namespace std
 	const locale& __loc = __io._M_getloc();
 	const __cache_type* __lc = __uc(__loc);
 
-	// Note: digits10 is rounded down: add 1 to ensure the maximum
-	// available precision.  Then, in general, one more 1 needs to
-	// be added since, when the %{g,G} conversion specifiers are
-	// chosen inside _S_format_float, the precision field is "the
-	// maximum number of significant digits", *not* the "number of
-	// digits to appear after the decimal point", as happens for
-	// %{e,E,f,F} (C99, 7.19.6.1,4).
-	const int __max_digits = numeric_limits<_ValueT>::digits10 + 2;
-
 	// Use default precision if out of range.
 	streamsize __prec = __io.precision();
-	if (__prec > static_cast<streamsize>(__max_digits))
-	  __prec = static_cast<streamsize>(__max_digits);
-	else if (__prec < static_cast<streamsize>(0))
+	if (__prec < static_cast<streamsize>(0))
 	  __prec = static_cast<streamsize>(6);
 
+	const int __max_digits = numeric_limits<_ValueT>::digits10;
+
 	// [22.2.2.2.2] Stage 1, numeric conversion to character.
 	int __len;
 	// Long enough for the max format spec.
 	char __fbuf[16];
 
 #ifdef _GLIBCXX_USE_C99
-	// First try a buffer perhaps big enough (for sure sufficient
+	// First try a buffer perhaps big enough (most probably sufficient
 	// for non-ios_base::fixed outputs)
 	int __cs_size = __max_digits * 3;
 	char* __cs = static_cast<char*>(__builtin_alloca(__cs_size));
@@ -1097,13 +1088,13 @@ namespace std
 	const int __max_exp = numeric_limits<_ValueT>::max_exponent10;
 
 	// The size of the output string is computed as follows.
-	// ios_base::fixed outputs may need up to __max_exp+1 chars
-	// for the integer part + up to __max_digits chars for the
-	// fractional part + 3 chars for sign, decimal point, '\0'. On
-	// the other hand, for non-fixed outputs __max_digits*3 chars
-	// are largely sufficient.
-	const int __cs_size = __fixed ? __max_exp + __max_digits + 4
-	                              : __max_digits * 3;
+	// ios_base::fixed outputs may need up to __max_exp + 1 chars
+	// for the integer part + __prec chars for the fractional part
+	// + 3 chars for sign, decimal point, '\0'. On the other hand,
+	// for non-fixed outputs __max_digits * 2 + __prec chars are
+	// largely sufficient.
+	const int __cs_size = __fixed ? __max_exp + __prec + 4
+	                              : __max_digits * 2 + __prec;
 	char* __cs = static_cast<char*>(__builtin_alloca(__cs_size));
 
 	__num_base::_S_format_float(__io, __fbuf, __mod);
diff --git a/libstdc++-v3/testsuite/22_locale/num_put/put/char/14220.cc b/libstdc++-v3/testsuite/22_locale/num_put/put/char/14220.cc
new file mode 100644
index 0000000..ecaeec9
--- /dev/null
+++ b/libstdc++-v3/testsuite/22_locale/num_put/put/char/14220.cc
@@ -0,0 +1,49 @@
+// 2004-04-30  Paolo Carlini  <pcarlini@suse.de>
+
+// Copyright (C) 2004 Free Software Foundation
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 2, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING.  If not, write to the Free
+// Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307,
+// USA.
+
+// 22.2.2.2.1  num_put members
+
+#include <locale>
+#include <sstream>
+#include <testsuite_hooks.h>
+
+// libstdc++/14220
+void test01()
+{
+  using namespace std;
+  bool test __attribute__((unused)) = true;
+
+  ostringstream oss;
+  const num_put<char>& np = use_facet<num_put<char> >(oss.getloc());
+
+  const int precision = 1000;
+
+  oss.precision(precision);
+  oss.setf(ios_base::fixed);
+  np.put(oss.rdbuf(), oss, '+', 1.0);
+  const string result = oss.str();
+  VERIFY( result.size() == precision + 2 );
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/22_locale/num_put/put/wchar_t/14220.cc b/libstdc++-v3/testsuite/22_locale/num_put/put/wchar_t/14220.cc
new file mode 100644
index 0000000..1319e56
--- /dev/null
+++ b/libstdc++-v3/testsuite/22_locale/num_put/put/wchar_t/14220.cc
@@ -0,0 +1,49 @@
+// 2004-04-30  Paolo Carlini  <pcarlini@suse.de>
+
+// Copyright (C) 2004 Free Software Foundation
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 2, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING.  If not, write to the Free
+// Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307,
+// USA.
+
+// 22.2.2.2.1  num_put members
+
+#include <locale>
+#include <sstream>
+#include <testsuite_hooks.h>
+
+// libstdc++/14220
+void test01()
+{
+  using namespace std;
+  bool test __attribute__((unused)) = true;
+  
+  wostringstream oss;
+  const num_put<wchar_t>& np = use_facet<num_put<wchar_t> >(oss.getloc());
+
+  const int precision = 1000;
+
+  oss.precision(precision);
+  oss.setf(ios_base::fixed);
+  np.put(oss.rdbuf(), oss, L'+', 1.0);
+  const wstring result = oss.str();
+  VERIFY( result.size() == precision + 2 );
+}
+
+int main()
+{
+  test01();
+  return 0;
+}