diff --git a/include/stdarg.h b/include/stdarg.h
index 34061d06..08c5ded5 100644
--- a/include/stdarg.h
+++ b/include/stdarg.h
@@ -34,6 +34,8 @@
 typedef char *va_list;
 #define va_start(ap, last) (void)((ap) = (char*)(&(last) + 1))
 #define va_arg(ap, type) (type)(((long*)((ap) = ((ap) + sizeof (void*))))[-1])
+#define va_align(ap, alignment) ((((unsigned long) (unsigned char*) ap) + (alignment) - 1) &~ (alignment - 1))
+#define va_arg8(ap, type) (type)(((double*)((ap) = (va_align((ap), 8) + sizeof(double))))[-1])
 #define va_end(ap) (void)((ap) = 0)
 #define va_copy(dest, src) dest = src
 
diff --git a/lib/stdio/vfprintf.c b/lib/stdio/vfprintf.c
index 979ad8df..00ac4917 100644
--- a/lib/stdio/vfprintf.c
+++ b/lib/stdio/vfprintf.c
@@ -188,7 +188,7 @@ vfprintf (FILE * f, char const *format, va_list ap)
           case 'g':
           case 'G':
             {
-              double d = va_arg (ap, double);
+              double d = va_arg8 (ap, double);
               char *s = dtoab (d, 10, 1);
               if (c == 'E' || c == 'G')
                 strupr (s);
diff --git a/lib/stdio/vsnprintf.c b/lib/stdio/vsnprintf.c
index a8d9624d..b1ed2e0a 100644
--- a/lib/stdio/vsnprintf.c
+++ b/lib/stdio/vsnprintf.c
@@ -204,7 +204,7 @@ vsnprintf (char *str, size_t size, char const *format, va_list ap)
           case 'g':
           case 'G':
             {
-              double d = va_arg (ap, double);
+              double d = va_arg8 (ap, double);
               char *s = dtoab (d, 10, 1);
               if (c == 'E' || c == 'G')
                 strupr (s);