Fix for 32 bit, see: https://github.com/HDFGroup/hdf5/issues/4916

From 0af668f4091f1c35f621d2acdeadd34db6756976 Mon Sep 17 00:00:00 2001
From: Orion Poplawski <orion@nwra.com>
Date: Fri, 4 Oct 2024 13:33:15 -0600
Subject: [PATCH] Re-add call to AC_CHECK_SIZEOF([__float128]). Fixes #4916.
 (#4924)

---
 configure.ac | 1 +
 1 file changed, 1 insertion(+)

diff --git a/configure.ac b/configure.ac
index af6c974a2a0..c5bfe4276af 100644
--- a/configure.ac
+++ b/configure.ac
@@ -854,6 +854,7 @@ if test "X$HDF_FORTRAN" = "Xyes"; then
   if test "$MY_FLT128_DIG" -gt "$MY_LDBL_DIG" ; then
     AC_MSG_RESULT([yes])
     AC_DEFINE([HAVE_FLOAT128], [1], [Determine if __float128 will be used in the Fortran wrappers])
+    AC_CHECK_SIZEOF([__float128])
   else
     ## Can't use __float128, but write an undef line anyway
     AC_MSG_RESULT([no])