Mark sysv.S as SafeSEH compatible (#438)

It contains no exception handler, so we can just emit the special
@feat.00 symbol to indicate that it's trivially SafeSEH compatible.
SafeSEH only applies to x86 and not x86-64, hence its inclusion in the
x86-specific block. See [1] for details.

[1] https://msdn.microsoft.com/en-us/library/windows/desktop/ms680547(v=vs.85).aspx#the_.sxdata_section_

diff --git a/src/x86/sysv.S b/src/x86/sysv.S
index 27379a48a1ccdc5e2762a1b24510a243274e1c29..52f307a04876897a9de5e1f2fdd6049183f5a8d9 100644 (file)
--- a/src/x86/sysv.S
+++ b/src/x86/sysv.S
@@ -1035,6 +1035,15 @@ L(SFDE9):
 L(EFDE9):
 #endif /* !FFI_NO_RAW_API */
 
+#ifdef _WIN32
+       .def     @feat.00;
+       .scl    3;
+       .type   0;
+       .endef
+       .globl  @feat.00
+@feat.00 = 1
+#endif
+
 #endif /* ifndef _MSC_VER */
 #endif /* ifndef __x86_64__ */