(AC_CHECK_SIZEOF): Report an error if the size cannot be determined

even though the type exists.

diff --git a/lib/autoconf/types.m4 b/lib/autoconf/types.m4
index df8a5af2c3d711de757ded972e697df39078f605..c3cf62b41455d63948a455db988f09b516ce54cd 100644 (file)
--- a/lib/autoconf/types.m4
+++ b/lib/autoconf/types.m4
@@ -354,7 +354,8 @@ AC_CACHE_CHECK([size of $1], AS_TR_SH([ac_cv_sizeof_$1]),
 [if test "$AS_TR_SH([ac_cv_type_$1])" = yes; then
   _AC_COMPUTE_INT([sizeof ($1)],
                   [AS_TR_SH([ac_cv_sizeof_$1])],
-                  [AC_INCLUDES_DEFAULT([$3])])
+                  [AC_INCLUDES_DEFAULT([$3])],
+                  [AC_MSG_ERROR([cannot compute sizeof ($1), 77])])
 else
   AS_TR_SH([ac_cv_sizeof_$1])=0
 fi])dnl