Merge pull request #2788 in HDFFV/hdf5 from ~LRKNOX/hdf5_lrk:hdf5_1_8 to hdf5_1_8

* commit '4496516ceea24060b966b6b64f4affa2af48eab7':
  Remove unnecessary assignment freom configure.ac.
  Check for header szlib.h only when libsz passes AC_CHECK_LIB, so that H5_HAVE_SALIB_H is not defined when szip is not enabled, to prevent compile failures for incompatible szlib.

2 files changed, 23 insertions, 21 deletions

diff --git a/configure b/configure
index a7dd6ed..320d0bc 100755
--- a/configure
+++ b/configure
@@ -25679,27 +25679,13 @@ $as_echo "suppressed" >&6; }
       AM_CPPFLAGS="$AM_CPPFLAGS -I$szlib_inc"
     fi
 
-    for ac_header in szlib.h
-do :
-  ac_fn_c_check_header_mongrel "$LINENO" "szlib.h" "ac_cv_header_szlib_h" "$ac_includes_default"
-if test "x$ac_cv_header_szlib_h" = xyes; then :
-  cat >>confdefs.h <<_ACEOF
-#define HAVE_SZLIB_H 1
-_ACEOF
- HAVE_SZLIB_H="yes"
-else
-  CPPFLAGS="$saved_CPPFLAGS"; AM_CPPFLAGS="$saved_AM_CPPFLAGS" unset HAVE_SZLIB
-fi
-
-done
-
 
     if test -n "$szlib_lib"; then
       LDFLAGS="$LDFLAGS -L$szlib_lib"
       AM_LDFLAGS="$AM_LDFLAGS -L$szlib_lib"
     fi
 
-    if test "x$HAVE_SZLIB" = "xyes" -a "x$HAVE_SZLIB_H" = "xyes"; then
+    if test "x$HAVE_SZLIB" = "xyes"; then
       { $as_echo "$as_me:${as_lineno-$LINENO}: checking for SZ_BufftoBuffCompress in -lsz" >&5
 $as_echo_n "checking for SZ_BufftoBuffCompress in -lsz... " >&6; }
 if ${ac_cv_lib_sz_SZ_BufftoBuffCompress+:} false; then :
@@ -25755,7 +25741,22 @@ else
   CPPFLAGS="$saved_CPPFLAGS"; AM_CPPFLAGS="$saved_AM_CPPFLAGS"; LDFLAGS="$saved_LDFLAGS"; AM_LDFLAGS="$saved_AM_LDFLAGS"; unset HAVE_SZLIB
 fi
 
-      if test -z "$HAVE_SZLIB"; then
+      if test -n "$HAVE_SZLIB"; then
+        for ac_header in szlib.h
+do :
+  ac_fn_c_check_header_mongrel "$LINENO" "szlib.h" "ac_cv_header_szlib_h" "$ac_includes_default"
+if test "x$ac_cv_header_szlib_h" = xyes; then :
+  cat >>confdefs.h <<_ACEOF
+#define HAVE_SZLIB_H 1
+_ACEOF
+ HAVE_SZLIB_H="yes"
+else
+  CPPFLAGS="$saved_CPPFLAGS"; AM_CPPFLAGS="$saved_AM_CPPFLAGS" unset HAVE_SZLIB
+fi
+
+done
+
+      else
         { $as_echo "$as_me:${as_lineno-$LINENO}: result: Using SZ_BufftoBuffCompress from libsz in $szlib_lib failed.  Szip not enabled." >&5
 $as_echo "Using SZ_BufftoBuffCompress from libsz in $szlib_lib failed.  Szip not enabled." >&6; }
       fi
diff --git a/configure.ac b/configure.ac
index 8bb3636..1f685b2 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1395,19 +1395,20 @@ case "X-$withval" in
       AM_CPPFLAGS="$AM_CPPFLAGS -I$szlib_inc"
     fi
 
-    AC_CHECK_HEADERS([szlib.h],
-                     [HAVE_SZLIB_H="yes"],
-                     [CPPFLAGS="$saved_CPPFLAGS"; AM_CPPFLAGS="$saved_AM_CPPFLAGS"] [unset HAVE_SZLIB])
 
     if test -n "$szlib_lib"; then
       LDFLAGS="$LDFLAGS -L$szlib_lib"
       AM_LDFLAGS="$AM_LDFLAGS -L$szlib_lib"
     fi
 
-    if test "x$HAVE_SZLIB" = "xyes" -a "x$HAVE_SZLIB_H" = "xyes"; then
+    if test "x$HAVE_SZLIB" = "xyes"; then
       AC_CHECK_LIB([sz], [SZ_BufftoBuffCompress],,
                    [CPPFLAGS="$saved_CPPFLAGS"; AM_CPPFLAGS="$saved_AM_CPPFLAGS"; LDFLAGS="$saved_LDFLAGS"; AM_LDFLAGS="$saved_AM_LDFLAGS"; unset HAVE_SZLIB])
-      if test -z "$HAVE_SZLIB"; then
+      if test -n "$HAVE_SZLIB"; then
+        AC_CHECK_HEADERS([szlib.h],
+                     [HAVE_SZLIB_H="yes"],
+                     [CPPFLAGS="$saved_CPPFLAGS"; AM_CPPFLAGS="$saved_AM_CPPFLAGS"] [unset HAVE_SZLIB])
+      else
         AC_MSG_RESULT([Using SZ_BufftoBuffCompress from libsz in $szlib_lib failed.  Szip not enabled.])
       fi
     fi