Fixes and cleanup for ph5diff (HDFGroup#4460)

* Fixes and cleanup for ph5diff

Fixes concurrency issues in ph5diff that can cause interleaved
output

Fixes an issue where output can sometimes be dropped if it ended
up in ph5diff's output overflow file

Fixes an issue where MPI_Init is called after HDF5 has been
initialized, preventing the library from setting up an MPI
attribute to perform cleanup on MPI_Finalize

Fixes an issue in config/cmake/runTest.cmake where the CMake
logic would try to access an invalid list index if the number
of lines in a test's output and reference files don't match

* Add release note

config/cmake/runTest.cmake

@@ -265,12 +265,22 @@ if (NOT TEST_SKIP_COMPARE)
           endif ()
           math (EXPR _FP_LEN "${len_ref} - 1")
           foreach (line RANGE 0 ${_FP_LEN})
-            list (GET test_act ${line} str_act)
-            list (GET test_ref ${line} str_ref)
-            if (NOT str_act STREQUAL str_ref)
-              if (str_act)
-                set (TEST_COMPARE_RESULT 1)
-                message (STATUS "line = ${line}\n***ACTUAL: ${str_act}\n****REFER: ${str_ref}\n")
+            if (line GREATER_EQUAL len_act)
+              message (STATUS "COMPARE FAILED: ran out of lines in ${TEST_FOLDER}/${TEST_OUTPUT}")
+              set (TEST_COMPARE_RESULT 1)
+              break ()
+            elseif (line GREATER_EQUAL len_ref)
+              message (STATUS "COMPARE FAILED: ran out of lines in ${TEST_FOLDER}/${TEST_REFERENCE}")
+              set (TEST_COMPARE_RESULT 1)
+              break ()
+            else ()
+              list (GET test_act ${line} str_act)
+              list (GET test_ref ${line} str_ref)
+              if (NOT str_act STREQUAL str_ref)
+                if (str_act)
+                  set (TEST_COMPARE_RESULT 1)
+                  message (STATUS "line = ${line}\n***ACTUAL: ${str_act}\n****REFER: ${str_ref}\n")
+                endif ()
               endif ()
             endif ()
           endforeach ()

release_docs/RELEASE.txt

@@ -747,20 +747,6 @@ Support for new platforms, languages and compilers
 
 Bug Fixes since HDF5-1.14.0 release
 ===================================
-    Configuration:
-    -------------
-    - Fix Autotools -Werror cleanup
-
-      The Autotools temporarily scrub -Werror(=whatever) from CFLAGS, etc.
-      so configure checks don't trip over warnings generated by configure
-      check programs. The sed line originally only scrubbed -Werror but not
-      -Werror=something, which would cause errors when the '=something' was
-      left behind in CFLAGS.
-
-      The sed line has been updated to handle -Werror=something lines.
-
-      Fixes one issue raised in #3872
-
     Library
     -------
 
@@ -1672,6 +1658,24 @@ Bug Fixes since HDF5-1.14.0 release
 
     Configuration
     -------------
+    - Fixed a list index out of range issue in the runTest.cmake file
+
+      Fixed an issue in config/cmake/runTest.cmake where the CMake logic
+      would try to access an invalid list index if the number of lines in
+      a test's output and reference files don't match
+
+    - Fix Autotools -Werror cleanup
+
+      The Autotools temporarily scrub -Werror(=whatever) from CFLAGS, etc.
+      so configure checks don't trip over warnings generated by configure
+      check programs. The sed line originally only scrubbed -Werror but not
+      -Werror=something, which would cause errors when the '=something' was
+      left behind in CFLAGS.
+
+      The sed line has been updated to handle -Werror=something lines.
+
+      Fixes one issue raised in #3872
+
     - Changed default of 'Error on HDF5 doxygen warnings' DOXYGEN_WARN_AS_ERROR option.
 
       The default setting of DOXYGEN_WARN_AS_ERROR to 'FAIL_ON_WARNINGS' has been changed
@@ -1792,12 +1796,24 @@ Bug Fixes since HDF5-1.14.0 release
 
     Tools
     -----
+    - Fixed several issues in ph5diff
+
+      The parallel logic for the ph5diff tool inside the shared h5diff code was
+      refactored and cleaned up to fix several issues with the ph5diff tool. This
+      fixed:
+
+        - several concurrency issues in ph5diff that can result in interleaved
+          output
+        - an issue where output can sometimes be dropped when it ends up in
+          ph5diff's output overflow file
+        - an issue where MPI_Init was called after HDF5 had been initialized,
+          preventing the library from setting up an MPI communicator attribute
+          to perform library cleanup on MPI_Finalize
 
     - Renamed h5fuse.sh to h5fuse
 
       Addresses Discussion #3791
 
-
     - Fixed an issue with unmatched MPI messages in ph5diff
 
       The "manager" MPI rank in ph5diff was unintentionally sending "program end"