_toupper($1)], [$3])) AC_CACHE_CHECK( [for$1], [py_var], [AC_COMPILE_IFELSE( [AC_LANG_PROGRAM([$2], [void *x=$1])], [AS_VAR_SET([pyvar], [yes)], [AS_VARSET([py_var], [no]])] ) AS_VAR_IF( [py_var], [yes], ...