C++ warning and build fixes (#707)

* Committing clang-format changes

* C++ build and warning updates

* Fixes all warnings on C++ (with gcc 9.3)
* Updates CMake and Autotools C++ builds

* Undo warning clobber

Co-authored-by: github-actions <41898282+github-actions[bot]@users.noreply.github.com>

3 files changed, 10 insertions, 13 deletions

diff --git a/hl/c++/src/H5PacketTable.cpp b/hl/c++/src/H5PacketTable.cpp
index 0f47b0d..3fcc9b2 100644
--- a/hl/c++/src/H5PacketTable.cpp
+++ b/hl/c++/src/H5PacketTable.cpp
@@ -32,15 +32,13 @@
  * Opens an existing packet table, which can contain either fixed-length or
  * variable-length packets.
  */
-PacketTable::PacketTable(hid_t fileID, const char *name)
+PacketTable::PacketTable(hid_t fileID, const char *name) : table_id{H5PTopen(fileID, name)}
 {
-    table_id = H5PTopen(fileID, name);
 }
 
 /* "Open" Constructor - will be deprecated because of char* name */
-PacketTable::PacketTable(hid_t fileID, char *name)
+PacketTable::PacketTable(hid_t fileID, char *name) : table_id{H5PTopen(fileID, name)}
 {
-    table_id = H5PTopen(fileID, name);
 }
 
 /* Destructor
@@ -271,7 +269,7 @@ FL_PacketTable::GetPackets(hsize_t startIndex, hsize_t endIndex, void *data)
     if (startIndex > endIndex)
         return -1;
 
-    return H5PTread_packets(table_id, startIndex, (size_t)(endIndex - startIndex + 1), data);
+    return H5PTread_packets(table_id, startIndex, static_cast<size_t>(endIndex - startIndex + 1), data);
 }
 
 /* GetNextPacket (single packet)
diff --git a/hl/c++/src/H5PacketTable.h b/hl/c++/src/H5PacketTable.h
index acd0ccf..306cc2f 100644
--- a/hl/c++/src/H5PacketTable.h
+++ b/hl/c++/src/H5PacketTable.h
@@ -33,9 +33,8 @@ class H5_HLCPPDLL PacketTable {
     /* Null constructor
      * Sets table_id to "invalid"
      */
-    PacketTable()
+    PacketTable() : table_id{H5I_INVALID_HID}
     {
-        table_id = H5I_INVALID_HID;
     }
 
     /* "Open" Constructor
diff --git a/hl/c++/test/ptableTest.cpp b/hl/c++/test/ptableTest.cpp
index 2600367..6deb24d 100644
--- a/hl/c++/test/ptableTest.cpp
+++ b/hl/c++/test/ptableTest.cpp
@@ -307,7 +307,7 @@ TestCompress()
         if (HDstrncmp(filter_name, "deflate", 7) != 0)
             H5_FAILED()
     }
-    catch (Exception e) {
+    catch (Exception const &) {
         H5_FAILED();
         return 1;
     }
@@ -605,8 +605,8 @@ const int     STRING_LENGTH = 19; // including terminating NULL
 int
 TestHDFFV_9758()
 {
-    hid_t  strtype;
-    hid_t  compound_type;
+    hid_t  strtype       = H5I_INVALID_HID;
+    hid_t  compound_type = H5I_INVALID_HID;
     herr_t err;
     struct s1_t {
         int    a;
@@ -620,9 +620,9 @@ TestHDFFV_9758()
 
     for (hsize_t i = 0; i < NUM_PACKETS; i++) {
         s1[i].a = static_cast<int>(i);
-        s1[i].b = 1.f * static_cast<float>(i * i);
-        s1[i].c = 1. / (i + 1);
-        HDsprintf(s1[i].d, "string%d", (int)i);
+        s1[i].b = 1.0f * static_cast<float>(i * i);
+        s1[i].c = 1.0 / static_cast<double>(i + 1);
+        HDsprintf(s1[i].d, "string%" PRIuHSIZE "", i);
         s1[i].e = static_cast<int>(100 + i);
     }