Check for COFF type directive, and use in assembly RPOLOGUE.

Fixes problem with windows dll linking.

ChangeLog

 2014-05-31  Niels Möller  <nisse@lysator.liu.se>
 
+	* configure.ac: Check for COFF type directives.
+	(ASM_COFF_STYLE): New substituted variable.
+	* config.m4.in: Set COFF_STYLE from configure.
+	* asm.m4 (PROLOGUE): Use COFF type directive, if enabled by
+	configure. Fixes problem with windows dll linking.
+
 	* asm.m4: Deleted unused offsets for struct aes_ctx.
 
 2014-05-28  Niels Möller  <nisse@lysator.liu.se>

asm.m4

@@ -19,6 +19,13 @@ define(<PROLOGUE>,
 <.globl C_NAME($1)
 .type C_NAME($1),TYPE_FUNCTION
 C_NAME($1):>,
+COFF_STYLE, <yes>,
+<.globl C_NAME($1)
+.def C_NAME($1)
+.scl 2
+.type 32
+.endef
+C_NAME($1):>,
 <.globl C_NAME($1)
 C_NAME($1):>)>)
 

config.m4.in

 define(<srcdir>, <<@srcdir@>>)dnl
 define(<C_NAME>, <@ASM_SYMBOL_PREFIX@><$1>)dnl
 define(<ELF_STYLE>, <@ASM_ELF_STYLE@>)dnl
+define(<COFF_STYLE>, <@ASM_COFF_STYLE@>)dnl
 define(<TYPE_FUNCTION>, <@ASM_TYPE_FUNCTION@>)dnl
 define(<TYPE_PROGBITS>, <@ASM_TYPE_PROGBITS@>)dnl
 define(<ALIGN_LOG>, <@ASM_ALIGN_LOG@>)dnl

configure.ac

@@ -487,6 +487,7 @@ AC_SUBST([CCPIC_MAYBE])
 
 ASM_SYMBOL_PREFIX=''
 ASM_ELF_STYLE='no'
+ASM_COFF_STYLE='no'
 # GNU as default is to use @
 ASM_TYPE_FUNCTION='@function'
 ASM_TYPE_PROGBITS='@progbits'
@@ -554,6 +555,23 @@ foo:
     fi
   fi
 
+  AC_CACHE_CHECK([for COFF-style .type directive],
+    [nettle_cv_asm_coff_type],
+      [GMP_TRY_ASSEMBLE([
+.text
+.globl _foo
+.def _foo
+.scl 2
+.type 32
+.endef
+_foo:
+],
+        [nettle_cv_asm_coff_type=yes],
+        [nettle_cv_asm_coff_type=no])])
+  if test "x$nettle_cv_asm_coff_type" = "xyes" ; then
+    ASM_COFF_STYLE=yes
+  fi
+
   AC_CACHE_CHECK([if we should use a .note.GNU-stack section],
   nettle_cv_asm_gnu_stack,
   [ # Default
@@ -589,6 +607,7 @@ fi
 
 AC_SUBST(ASM_SYMBOL_PREFIX)
 AC_SUBST(ASM_ELF_STYLE)
+AC_SUBST(ASM_COFF_STYLE)
 AC_SUBST(ASM_TYPE_FUNCTION)
 AC_SUBST(ASM_TYPE_PROGBITS)
 AC_SUBST(ASM_MARK_NOEXEC_STACK)