msvcrt: Implement longjmp for x86_64.
diff --git a/dlls/msvcr90/msvcr90.spec b/dlls/msvcr90/msvcr90.spec
index 49b7139..c89bfda 100644
--- a/dlls/msvcr90/msvcr90.spec
+++ b/dlls/msvcr90/msvcr90.spec
@@ -1360,7 +1360,7 @@
 @ cdecl localeconv() msvcrt.localeconv
 @ cdecl log(double) msvcrt.log
 @ cdecl log10(double) msvcrt.log10
-@ cdecl -i386 longjmp(ptr long) msvcrt.longjmp
+@ cdecl -arch=i386,x86_64 longjmp(ptr long) msvcrt.longjmp
 @ cdecl malloc(long) msvcrt.malloc
 @ cdecl mblen(ptr long) msvcrt.mblen
 @ stub mbrlen