From 7e4844b35371bcfd5cdff688a9d7346f8e982211 Mon Sep 17 00:00:00 2001
From: Howard Hinnant <hhinnant@apple.com>
Date: Fri, 8 Mar 2013 19:06:24 +0000
Subject: [PATCH] Parsing floating point numbers with very long precision was
 broken, and this patch fixes it.  This fixes
 http://llvm.org/bugs/show_bug.cgi?id=15445.

llvm-svn: 176711
---
 libcxx/include/locale                                | 20 +++++++++++++-------
 .../facet.num.get.members/get_double.pass.cpp        | 12 ++++++++++++
 2 files changed, 25 insertions(+), 7 deletions(-)

diff --git a/libcxx/include/locale b/libcxx/include/locale
index 39aba84..8f9a3b6 100644
--- a/libcxx/include/locale
+++ b/libcxx/include/locale
@@ -646,6 +646,8 @@ __num_get<_CharT>::__stage2_float_loop(_CharT __ct, bool& __in_units, char& __ex
                     _CharT __decimal_point, _CharT __thousands_sep, const string& __grouping,
                     unsigned* __g, unsigned*& __g_end, unsigned& __dc, _CharT* __atoms)
 {
+    if (__a_end-__a >= __num_get_buf_sz - 1)
+        return -1;
     if (__ct == __decimal_point)
     {
         if (!__in_units)
@@ -673,23 +675,27 @@ __num_get<_CharT>::__stage2_float_loop(_CharT __ct, bool& __in_units, char& __ex
     char __x = __src[__f];
     if (__x == '-' || __x == '+')
     {
-        if (__a_end == __a || (__a_end[-1] & 0xDF) == __exp)
+        if (__a_end == __a || (__a_end[-1] & 0x5F) == (__exp & 0x7F))
         {
             *__a_end++ = __x;
             return 0;
         }
         return -1;
     }
-    if (__a_end-__a < __num_get_buf_sz - 1)
-        *__a_end++ = __x;
     if (__x == 'x' || __x == 'X')
         __exp = 'P';
-    else if ((__x & 0xDF) == __exp)
+    else if ((__x & 0x5F) == __exp)
     {
-        __in_units = false;
-        if (__grouping.size() != 0 && __g_end-__g < __num_get_buf_sz)
-            *__g_end++ = __dc;
+        __exp |= 0x80;
+        if (__in_units)
+        {
+            __in_units = false;
+            if (__grouping.size() != 0 && __g_end-__g < __num_get_buf_sz)
+                *__g_end++ = __dc;
+        }
     }
+    if (__a_end-__a < __num_get_buf_sz - ((__exp & 0x80) ? 1 : 11))
+        *__a_end++ = __x;
     if (__f >= 22)
         return 0;
     ++__dc;
diff --git a/libcxx/test/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_double.pass.cpp b/libcxx/test/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_double.pass.cpp
index 58c9b2d..4e0f2b8 100644
--- a/libcxx/test/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_double.pass.cpp
+++ b/libcxx/test/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_double.pass.cpp
@@ -240,4 +240,16 @@ int main()
         assert(iter.base() == str+sizeof(str)-1);
         assert(err == ios.failbit);
     }
+    {
+        v = -1;
+        const char str[] = "3;14159265358979323846264338327950288419716939937510582097494459230781640628620899862803482534211706798214808651e+10";
+        std::ios_base::iostate err = ios.goodbit;
+        input_iterator<const char*> iter =
+            f.get(input_iterator<const char*>(str),
+                  input_iterator<const char*>(str+sizeof(str)),
+                  ios, err, v);
+        assert(iter.base() == str+sizeof(str)-1);
+        assert(err == ios.goodbit);
+        assert(std::abs(v - 3.14159265358979e+10)/3.14159265358979e+10 < 1.e-8);
+    }
 }
-- 
2.7.4