* vsnprintf.c (BSD_vfprintf): fix precision specifier doesn't

work well on %f. [ruby-dev:42552]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@29719 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ChangeLog

@@ -1,3 +1,8 @@
+Mon Nov  8 15:40:56 2010  NARUSE, Yui  <naruse@ruby-lang.org>
+
+	* vsnprintf.c (BSD_vfprintf): fix precision specifier doesn't
+	  work well on %f. [ruby-dev:42552]
+
 Mon Nov  8 14:41:40 2010  NAKAMURA Usaku  <usa@ruby-lang.org>
 
 	* win32/win32.c (get_wsa_extension_function): typos.

test/ruby/test_sprintf.rb

@@ -189,6 +189,7 @@ class TestSprintf < Test::Unit::TestCase
     assert_equal("36893488147419111424",
                  sprintf("%20.0f", 36893488147419107329.0))
     assert_equal(" Inf", sprintf("% 0e", 1.0/0.0), "moved from btest/knownbug")
+    assert_equal("       -0.", sprintf("%#10.0f", -0.5), "[ruby-dev:42552]")
   end
 
   def test_float_hex

vsnprintf.c

@@ -855,6 +855,8 @@ fp_begin:		_double = va_arg(ap, double);
 						size += prec + 1;
 				} else if (!prec) { /* "0" */
 					size = 1;
+					if (flags & ALT)
+						size += 1;
 				} else	/* "0.X" */
 					size = prec + 2;
 			} else if (expt >= ndig) {	/* fixed g fmt */