diff --git a/.github/workflows/data/expat_config_h_in__expected.txt b/.github/workflows/data/expat_config_h_in__expected.txt
index 3c23e8fc..56f66137 100644
--- a/.github/workflows/data/expat_config_h_in__expected.txt
+++ b/.github/workflows/data/expat_config_h_in__expected.txt
@@ -29,6 +29,7 @@ PACKAGE_STRING
 PACKAGE_TARNAME
 PACKAGE_URL
 PACKAGE_VERSION
+SIZEOF_VOID_P
 size_t
 STDC_HEADERS
 VERSION
diff --git a/expat/cmake/autotools/expat-config-version.cmake.in b/expat/cmake/autotools/expat-config-version.cmake.in
index 798d861d..5b296752 100644
--- a/expat/cmake/autotools/expat-config-version.cmake.in
+++ b/expat/cmake/autotools/expat-config-version.cmake.in
@@ -55,13 +55,13 @@ if("FALSE")
 endif()
 
 # if the installed or the using project don't have CMAKE_SIZEOF_VOID_P set, ignore it:
-if("${CMAKE_SIZEOF_VOID_P}" STREQUAL "" OR "8" STREQUAL "")
+if("${CMAKE_SIZEOF_VOID_P}" STREQUAL "" OR "@ac_cv_sizeof_void_p@" STREQUAL "")
   return()
 endif()
 
 # check that the installed version has the same 32/64bit-ness as the one which is currently searching:
-if(NOT CMAKE_SIZEOF_VOID_P STREQUAL "8")
-  math(EXPR installedBits "8 * 8")
+if(NOT CMAKE_SIZEOF_VOID_P STREQUAL "@ac_cv_sizeof_void_p@")
+  math(EXPR installedBits "@ac_cv_sizeof_void_p@ * 8")
   set(PACKAGE_VERSION "${PACKAGE_VERSION} (${installedBits}bit)")
   set(PACKAGE_VERSION_UNSUITABLE TRUE)
 endif()
diff --git a/expat/configure.ac b/expat/configure.ac
index 7d60a2c2..6ba69a2e 100644
--- a/expat/configure.ac
+++ b/expat/configure.ac
@@ -372,6 +372,7 @@ LIBDIR_BASENAME="$(basename "${libdir}")"
 SO_MAJOR="$(expr "${LIBCURRENT}" - "${LIBAGE}")"
 SO_MINOR="${LIBAGE}"
 SO_PATCH="${LIBREVISION}"
+AC_CHECK_SIZEOF([void *])  # sets ac_cv_sizeof_void_p
 AC_SUBST([EXPAT_ATTR_INFO])
 AC_SUBST([EXPAT_DTD])
 AC_SUBST([EXPAT_LARGE_SIZE])
@@ -384,6 +385,7 @@ AC_SUBST([LIBDIR_BASENAME])
 AC_SUBST([SO_MAJOR])
 AC_SUBST([SO_MINOR])
 AC_SUBST([SO_PATCH])
+AC_SUBST([ac_cv_sizeof_void_p])
 
 
 dnl write the Automake flags we set