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+dnl @synopsis AX_EMPTY_ARRAY
+dnl
+dnl Define EMPTY_ARRAY_SIZE to be either "0"
+dnl or "" depending on which syntax the compiler
+dnl prefers for empty arrays in structs.
+dnl
+dnl @version
+dnl @author James Yonan <jim@yonan.net>
+AC_DEFUN([AX_EMPTY_ARRAY], [
+ AS_VAR_PUSHDEF([VAR],[ax_cv_c_empty_array])dnl
+ AC_CACHE_CHECK(
+ [for C compiler empty array size],
+ [VAR],
+ [AC_COMPILE_IFELSE(
+ [AC_LANG_PROGRAM(
+ ,
+ [[
+struct { int foo; int bar[0]; } mystruct;
+ ]]
+ )],
+ [VAR=0],
+ [AC_COMPILE_IFELSE(
+ [AC_LANG_PROGRAM(
+ ,
+ [[
+struct { int foo; int bar[]; } mystruct;
+ ]]
+ )],
+ [VAR=],
+ [AC_MSG_ERROR([C compiler is unable to creaty empty arrays])]
+ )]
+ )]
+ )dnl
+ AC_DEFINE_UNQUOTED(
+ [EMPTY_ARRAY_SIZE],
+ [$VAR],
+ [Dimension to use for empty array declaration]
+ )dnl
+ AS_VAR_POPDEF([VAR])dnl
+])