diff --git a/src/Config.cpp b/src/Config.cpp
index 3da32d102..1bfa69cc6 100644
--- a/src/Config.cpp
+++ b/src/Config.cpp
@@ -578,7 +578,7 @@ double Config::getReal (const std::string& key)
     return getReal("urgency.next.coefficient");
 
   if ((*this).find (key) != (*this).end ())
-    return std::stod ((*this)[key]);
+    return strtod ((*this)[key].c_str (), NULL);
 
   return 0.0;
 }
diff --git a/src/ISO8601.cpp b/src/ISO8601.cpp
index 3a6e5d60d..0acd8adc9 100644
--- a/src/ISO8601.cpp
+++ b/src/ISO8601.cpp
@@ -1874,7 +1874,7 @@ bool ISO8601p::parse (const std::string& input, std::string::size_type& start)
           Lexer::isSingleCharOperator (n.next ()))
       {
         start = original_start + n.cursor ();
-        double quantity = std::stod (number);
+        double quantity = strtod (number.c_str (), NULL);
 
         // Linear lookup - should instead be logarithmic.
         double seconds = 1;
diff --git a/src/ISO8601.h b/src/ISO8601.h
index 4bc3acd37..ddc661914 100644
--- a/src/ISO8601.h
+++ b/src/ISO8601.h
@@ -27,7 +27,6 @@
 #ifndef INCLUDED_ISO8601
 #define INCLUDED_ISO8601
 
-#include <string>
 #include <Nibbler.h>
 #include <time.h>
 
diff --git a/src/Variant.cpp b/src/Variant.cpp
index 6d0434468..515999238 100644
--- a/src/Variant.cpp
+++ b/src/Variant.cpp
@@ -25,12 +25,12 @@
 ////////////////////////////////////////////////////////////////////////////////
 
 #include <cmake.h>
-#include <Variant.h>
 #include <sstream>
 #include <algorithm>
 #include <stdio.h>
 #include <math.h>
 #include <stdlib.h>
+#include <Variant.h>
 #include <ISO8601.h>
 #include <Lexer.h>
 #include <RX.h>
@@ -1873,8 +1873,8 @@ void Variant::cast (const enum type new_type)
     case type_integer:
       _integer = (int) strtol (_string.c_str (), NULL, (_string.substr (0, 2) == "0x" ? 16 : 10));
       break;
-    case type_real:     _real = std::stod (_string);         break;
-    case type_string:                                        break;
+    case type_real:     _real = strtod (_string.c_str (), NULL);              break;
+    case type_string:                                                         break;
     case type_date:
       {
         _date = 0;