Lots of OS/2 updates

[wxWidgets.git] / acinclude.m4

diff --git a/acinclude.m4 b/acinclude.m4
index 4f7ee95a2bc149b859d3f6506e6038fd0c47aee7..6479c8eaab3fef41ea3601468cada6a873018e60 100644 (file)
--- a/acinclude.m4
+++ b/acinclude.m4
@@ -144,6 +144,53 @@ AC_DEFUN([WX_CPP_BOOL],
   fi
 ])
 
+dnl ---------------------------------------------------------------------------
+dnl WX_CPP_EXPLICIT checks whether the C++ compiler support the explicit
+dnl keyword and defines HAVE_EXPLICIT if this is the case
+dnl ---------------------------------------------------------------------------
+
+AC_DEFUN([WX_CPP_EXPLICIT],
+[
+  AC_CACHE_CHECK([if C++ compiler supports the explicit keyword],
+                 wx_cv_explicit,
+  [
+    AC_LANG_SAVE
+    AC_LANG_CPLUSPLUS
+
+    dnl do the test in 2 steps: first check that the compiler knows about the
+    dnl explicit keyword at all and then verify that it really honours it
+    AC_TRY_COMPILE(
+      [
+        class Foo { public: explicit Foo(int) {} };
+      ],
+      [
+        return 0;
+      ],
+      [
+        AC_TRY_COMPILE(
+            [
+                class Foo { public: explicit Foo(int) {} };
+                static void TakeFoo(const Foo& foo) { }
+            ],
+            [
+                TakeFoo(17);
+                return 0;
+            ],
+            wx_cv_explicit=no,
+            wx_cv_explicit=yes
+        )
+      ],
+      wx_cv_explicit=no
+    )
+
+    AC_LANG_RESTORE
+  ])
+
+  if test "$wx_cv_explicit" = "yes"; then
+    AC_DEFINE(HAVE_EXPLICIT)
+  fi
+])
+
 dnl ---------------------------------------------------------------------------
 dnl a slightly better AC_C_BIGENDIAN macro which allows cross-compiling
 dnl ---------------------------------------------------------------------------
@@ -409,3 +456,65 @@ size_t iconv();
   AC_SUBST(LIBICONV)
 ])
 
+dnl ---------------------------------------------------------------------------
+dnl AC_SYS_LARGEFILE (partly based on the code from autoconf 2.5x)
+dnl ---------------------------------------------------------------------------
+
+dnl WX_SYS_LARGEFILE_TEST
+dnl
+dnl NB: original autoconf test was checking if compiler supported 6 bit off_t
+dnl     arithmetic properly but this failed miserably with gcc under Linux
+dnl     whereas the system still supports 64 bit files, so now simply check
+dnl     that off_t is big enough
+define(WX_SYS_LARGEFILE_TEST,
+[typedef struct {
+    unsigned int field: sizeof(off_t) == 8;
+} wxlf;
+])
+
+
+dnl WX_SYS_LARGEFILE_MACRO_VALUE(C-MACRO, VALUE, CACHE-VAR)
+define(WX_SYS_LARGEFILE_MACRO_VALUE,
+[
+    AC_CACHE_CHECK([for $1 value needed for large files], [$3],
+        [
+          AC_TRY_COMPILE([#define $1 $2
+                          #include <sys/types.h>],
+                         WX_SYS_LARGEFILE_TEST,
+                         [$3=$2],
+                         [$3=no])
+        ]
+    )
+
+    if test "$$3" != no; then
+        wx_largefile=yes
+        AC_DEFINE_UNQUOTED([$1], [$$3])
+    fi
+])
+
+
+dnl AC_SYS_LARGEFILE
+dnl ----------------
+dnl By default, many hosts won't let programs access large files;
+dnl one must use special compiler options to get large-file access to work.
+dnl For more details about this brain damage please see:
+dnl http://www.sas.com/standards/large.file/x_open.20Mar96.html
+AC_DEFUN([AC_SYS_LARGEFILE],
+[AC_ARG_ENABLE(largefile,
+               [  --disable-largefile     omit support for large files])
+if test "$enable_largefile" != no; then
+    dnl _FILE_OFFSET_BITS==64 is needed for Linux, Solaris, ...
+    dnl _LARGE_FILES -- for AIX
+    wx_largefile=no
+    WX_SYS_LARGEFILE_MACRO_VALUE(_FILE_OFFSET_BITS, 64, ac_cv_sys_file_offset_bits)
+    if test "x$wx_largefile" != "xyes"; then
+        WX_SYS_LARGEFILE_MACRO_VALUE(_LARGE_FILES, 1, ac_cv_sys_large_files)
+    fi
+
+    AC_MSG_CHECKING(if large file support is available)
+    if test "x$wx_largefile" = "xyes"; then
+        AC_DEFINE(HAVE_LARGEFILE_SUPPORT)
+    fi
+    AC_MSG_RESULT($wx_largefile)
+fi
+])