gentoo-overlay/sci-libs/hdf/files/hdf-4.2.11-fix-szip-detection.patch

--- hdf-4.2.11.orig/configure.ac	2016-03-16 20:07:45.093493050 +0000
+++ hdf-4.2.11/configure.ac	2016-03-16 22:08:06.232711036 +0000
@@ -473,12 +473,14 @@
   yes)
     HAVE_SZIP="yes"
     AC_CHECK_HEADERS([szlib.h], [HAVE_SZLIB_H="yes"], [unset HAVE_SZIP])
-    if test "x$HAVE_SZLIB" = "xyes" -a "x$HAVE_SZLIB_H" = "xyes"; then
+    if test "x$HAVE_SZIP" = "xyes" -a "x$HAVE_SZLIB_H" = "xyes"; then
       AC_CHECK_LIB([sz], [SZ_BufftoBuffCompress],, [unset HAVE_SZIP])
     fi
 
     if test -z "$HAVE_SZIP"; then
       AC_MSG_ERROR([couldn't find szlib library])
+    else
+      USE_COMP_SZIP="yes"
     fi
     ;;
   no)
@@ -525,7 +527,7 @@
       AC_CHECK_LIB([sz], [SZ_BufftoBuffCompress],, [unset HAVE_SZIP])
     fi
 
-    if test -z "$HAVE_SZIP"; then
+    if test  "x$HAVE_SZIP" != "xyes"; then
       AC_MSG_ERROR([couldn't find szlib library])
     else
       USE_COMP_SZIP="yes"