Re: MSVC compiler support [patch 7]: mkdir number of arguments

[Michael Goffioul]

John W. Eaton a écrit :
> I would prefer to fix the test to make it work, so I'm not applying
> this patch.
>
> How does the current test fail?  I think the only place that this
> macro is used is liboctave/file-ops.cc.  Does that file fail to
> compile if MKDIR_TAKES_ONE_ARG is not defined?  If so, what is the
> error?
>   

The problem is that the test is done in C mode, while the code using it 
is C++. Under MSVC,
calling mkdir with 2 arguments in C mode only produces a warning, not a 
compilation error.
This is why the actual test does not work. I can understand the warning 
as calling a C function
with more arguments than expected is not as harmful as calling it with 
less arguments.

I can see 2 solutions:
1) do the test in the other way by testing mkdir() with one argument: 
this should produce an
error when 2 are required
2) switch to C++ mode when doing the test (see patch attached, it works OK)

Michael.

Index: aclocal.m4
===================================================================
RCS file: /cvs/octave/aclocal.m4,v
retrieving revision 1.98
diff -c -r1.98 aclocal.m4
*** aclocal.m4  18 Oct 2006 02:02:36 -0000      1.98
--- aclocal.m4  18 Oct 2006 12:04:58 -0000
***************
*** 784,791 ****
  dnl
  dnl Determine if mkdir accepts only one argument instead dnl of the usual 2.
  dnl
! AC_DEFUN(OCTAVE_MKDIR_TAKES_ONE_ARG,
! [AC_CACHE_CHECK([if mkdir takes one argument], octave_cv_mkdir_takes_one_arg,
  [AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[#include <sys/types.h>
  #ifdef HAVE_SYS_STAT_H
  # include <sys/stat.h>
--- 787,795 ----
  dnl
  dnl Determine if mkdir accepts only one argument instead dnl of the usual 2.
  dnl
! AC_DEFUN(OCTAVE_MKDIR_TAKES_ONE_ARG, [
! AC_LANG_PUSH(C++)
! AC_CACHE_CHECK([if mkdir takes one argument], octave_cv_mkdir_takes_one_arg,
  [AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[#include <sys/types.h>
  #ifdef HAVE_SYS_STAT_H
  # include <sys/stat.h>
***************
*** 797,802 ****
--- 801,807 ----
  # include <direct.h>
  #endif]], [[mkdir ("foo", 0);]])],
          octave_cv_mkdir_takes_one_arg=no, octave_cv_mkdir_takes_one_arg=yes)])
+ AC_LANG_POP(C++)
  if test $octave_cv_mkdir_takes_one_arg = yes ; then
    AC_DEFINE(MKDIR_TAKES_ONE_ARG, 1, [Define if host mkdir takes a single 
argument.])
  fi