--- a/config-site-generator/configure.ac
+++ b/config-site-generator/configure.ac
@@ -23,6 +23,7 @@ AC_DEFUN([AC_MSG_ERROR], [
     test -e conftest.dir && rm -rf conftest.dir ])
 
 # Checks for programs.
+AC_PROG_CC
 AC_PROG_CC_C89
 AC_PROG_CC_C_O
 AC_PROG_CPP
@@ -52,9 +53,11 @@ AC_PROG_LEX
 AC_PROG_LN_S
 AC_PROG_RANLIB
 AC_PROG_SED
+AC_PROG_LEX
 #AC_PROG_YACC
 
 AM_PROG_AS
+AM_PROG_AR
 
 # Checks for system services.
 #AC_PATH_X
@@ -118,6 +121,8 @@ sys/ucontext.h sys/uio.h sys/un.h sys/us
 sys/wait.h sys/xattr.h tar.h termios.h tgmath.h time.h ucontext.h ulimit.h \
 unistd.h utime.h utmp.h utmpx.h wchar.h wctype.h wordexp.h
 ])
+# extra headers
+AC_CHECK_HEADERS([sys/cdefs.h])
 
 # Checks for typedefs, structures, and compiler characteristics.
 AC_TYPE_GETGROUPS
@@ -217,6 +222,16 @@ AC_FUNC_STRTOLD
 AC_FUNC_UTIME_NULL
 AC_FUNC_VPRINTF
 
+AC_CHECK_SIZEOF(short)
+AC_CHECK_SIZEOF(int)
+AC_CHECK_SIZEOF(long)
+AC_CHECK_SIZEOF(long long)
+AC_CHECK_SIZEOF(unsigned int)
+AC_CHECK_SIZEOF(unsigned long)
+AC_CHECK_SIZEOF(unsigned long long)
+AC_CHECK_SIZEOF(off_t)
+AC_CHECK_SIZEOF(size_t)
+
 # Functions list scraped from musl 0.9.4 x86_64
 AC_CHECK_FUNCS([ \
 a64l abort abs accept access acos acosf acosh acoshf acoshl acosl addmntent \