Macro: ac_cxx_old_for_scoping

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# ac_cxx_old_for_scoping

## Synopsis

`AC_CXX_OLD_FOR_SCOPING`

## Version

1.1.1.1 (2001/07/26) C++_Support @ ac-archive-0.5.32

## Author

Luc Maisonobe

## Description

If the compiler accepts the old for scoping rules (the scope of a variable declared inside the parentheses extends outside the for-body), define HAVE_OLD_FOR_SCOPING. Note that some compilers (notably g++ and egcs) support both new and old rules since they accept the old rules and only generate a warning.

## M4 Source Code

    AC_DEFUN([AC_CXX_OLD_FOR_SCOPING],
    [AC_CACHE_CHECK(whether the compiler accepts the old for scoping rules,
    ac_cv_cxx_old_for_scoping,
    [AC_LANG_SAVE
     AC_LANG_CPLUSPLUS
     AC_TRY_COMPILE(,[int z;for (int i=0; i < 10; ++i)z=z+i;z=i;return z;],
     ac_cv_cxx_old_for_scoping=yes, ac_cv_cxx_old_for_scoping=no)
     AC_LANG_RESTORE
    ])
    if test "$ac_cv_cxx_old_for_scoping" = yes; then
      AC_DEFINE(HAVE_OLD_FOR_SCOPING,,[define if the compiler accepts the old for scoping rules])
    fi
    ])