Misc clang production warning fixes (#1932)

* Misc clang production warning fixes

* Committing clang-format changes

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

7 files changed, 79 insertions, 57 deletions

diff --git a/src/H5Cimage.c b/src/H5Cimage.c
index 2a94fca..da4ac33 100644
--- a/src/H5Cimage.c
+++ b/src/H5Cimage.c
@@ -2784,8 +2784,6 @@ H5C__prep_for_file_close__scan_entries(const H5F_t *f, H5C_t *cache_ptr)
     size_t             image_len;
     size_t             entry_header_len;
     size_t             fd_parents_list_len;
-    int                i;
-    unsigned           j;
     herr_t             ret_value = SUCCEED; /* Return value */
 
     FUNC_ENTER_PACKAGE
@@ -2862,7 +2860,7 @@ H5C__prep_for_file_close__scan_entries(const H5F_t *f, H5C_t *cache_ptr)
                         HGOTO_ERROR(H5E_CACHE, H5E_CANTALLOC, FAIL,
                                     "memory allocation failed for fd parent addrs buffer")
 
-                for (i = 0; i < (int)(entry_ptr->fd_parent_count); i++) {
+                for (int i = 0; i < (int)(entry_ptr->fd_parent_count); i++) {
                     entry_ptr->fd_parent_addrs[i] = entry_ptr->flush_dep_parent[i]->addr;
                     HDassert(H5F_addr_defined(entry_ptr->fd_parent_addrs[i]));
                 } /* end for */
@@ -2946,12 +2944,14 @@ H5C__prep_for_file_close__scan_entries(const H5F_t *f, H5C_t *cache_ptr)
     HDassert(entries_visited == cache_ptr->index_len);
     HDassert(num_entries_in_image <= num_entries_tentatively_in_image);
 
-    j = 0;
-    for (i = H5C_MAX_RING_IN_IMAGE + 1; i <= H5C_RING_SB; i++)
+#ifndef NDEBUG
+    unsigned j = 0;
+    for (int i = H5C_MAX_RING_IN_IMAGE + 1; i <= H5C_RING_SB; i++)
         j += cache_ptr->index_ring_len[i];
 
     /* This will change */
     HDassert(entries_visited == (num_entries_tentatively_in_image + j));
+#endif
 
     cache_ptr->num_entries_in_image = num_entries_in_image;
     entries_visited                 = 0;
diff --git a/src/H5FDmulti.c b/src/H5FDmulti.c
index 5f161aa..7849060 100644
--- a/src/H5FDmulti.c
+++ b/src/H5FDmulti.c
@@ -46,25 +46,30 @@
 
 /* Macros for enabling/disabling particular GCC / clang warnings
  *
- * These are (renamed) duplicates of macros in H5private.h. If you make changes
- * here, be sure to update those as well.
+ * These are duplicated in H5private.h. If you make changes here, be sure to
+ * update those as well.
  *
  * (see the following web-sites for more info:
  *      http://www.dbp-consulting.com/tutorials/SuppressingGCCWarnings.html
  *      http://gcc.gnu.org/onlinedocs/gcc/Diagnostic-Pragmas.html#Diagnostic-Pragmas
  */
-/* These pragmas are only implemented usefully in gcc 4.6+ */
-#if ((__GNUC__ * 100) + __GNUC_MINOR__) >= 406
-#define H5_MULTI_GCC_DIAG_JOINSTR(x, y) x y
-#define H5_MULTI_GCC_DIAG_DO_PRAGMA(x)  _Pragma(#x)
-#define H5_MULTI_GCC_DIAG_PRAGMA(x)     H5_MULTI_GCC_DIAG_DO_PRAGMA(GCC diagnostic x)
-
-#define H5_MULTI_GCC_DIAG_OFF(x)                                                                             \
-    H5_MULTI_GCC_DIAG_PRAGMA(push) H5_MULTI_GCC_DIAG_PRAGMA(ignored H5_MULTI_GCC_DIAG_JOINSTR("-W", x))
-#define H5_MULTI_GCC_DIAG_ON(x) H5_MULTI_GCC_DIAG_PRAGMA(pop)
+#define H5_MULTI_DIAG_JOINSTR(x, y) x y
+#define H5_MULTI_DIAG_DO_PRAGMA(x)  _Pragma(#x)
+#define H5_MULTI_DIAG_PRAGMA(x)     H5_MULTI_DIAG_DO_PRAGMA(GCC diagnostic x)
+
+#define H5_MULTI_DIAG_OFF(x)                                                                                 \
+    H5_MULTI_DIAG_PRAGMA(push) H5_MULTI_DIAG_PRAGMA(ignored H5_MULTI_DIAG_JOINSTR("-W", x))
+#define H5_MULTI_DIAG_ON(x) H5_MULTI_DIAG_PRAGMA(pop)
+
+/* Macros for enabling/disabling particular GCC / clang warnings.
+ * These macros should be used for warnings supported by both gcc and clang.
+ */
+#if (((__GNUC__ * 100) + __GNUC_MINOR__) >= 406) || defined(__clang__)
+#define H5_MULTI_GCC_CLANG_DIAG_OFF(x) H5_MULTI_DIAG_OFF(x)
+#define H5_MULTI_GCC_CLANG_DIAG_ON(x)  H5_MULTI_DIAG_ON(x)
 #else
-#define H5_MULTI_GCC_DIAG_OFF(x)
-#define H5_MULTI_GCC_DIAG_ON(x)
+#define H5_MULTI_GCC_CLANG_DIAG_OFF(x)
+#define H5_MULTI_GCC_CLANG_DIAG_ON(x)
 #endif
 
 /* Loop through all mapped files */
@@ -2125,7 +2130,7 @@ compute_next(H5FD_multi_t *file)
  *      tmp in the code below, but early (4.4.7, at least) gcc only
  *      allows diagnostic pragmas to be toggled outside of functions.
  */
-H5_MULTI_GCC_DIAG_OFF("format-nonliteral")
+H5_MULTI_GCC_CLANG_DIAG_OFF("format-nonliteral")
 static int
 open_members(H5FD_multi_t *file)
 {
@@ -2163,7 +2168,7 @@ open_members(H5FD_multi_t *file)
 
     return 0;
 }
-H5_MULTI_GCC_DIAG_ON("format-nonliteral")
+H5_MULTI_GCC_CLANG_DIAG_ON("format-nonliteral")
 
 /*-------------------------------------------------------------------------
  * Function:    H5FD_multi_delete
@@ -2174,7 +2179,7 @@ H5_MULTI_GCC_DIAG_ON("format-nonliteral")
  *
  *-------------------------------------------------------------------------
  */
-H5_MULTI_GCC_DIAG_OFF("format-nonliteral")
+H5_MULTI_GCC_CLANG_DIAG_OFF("format-nonliteral")
 static herr_t
 H5FD_multi_delete(const char *filename, hid_t fapl_id)
 {
@@ -2228,7 +2233,7 @@ H5FD_multi_delete(const char *filename, hid_t fapl_id)
 
     return 0;
 } /* end H5FD_multi_delete() */
-H5_MULTI_GCC_DIAG_ON("format-nonliteral")
+H5_MULTI_GCC_CLANG_DIAG_ON("format-nonliteral")
 
 /*-------------------------------------------------------------------------
  * Function:    H5FD_multi_ctl
diff --git a/src/H5HLcache.c b/src/H5HLcache.c
index 4d78d0c..620704a 100644
--- a/src/H5HLcache.c
+++ b/src/H5HLcache.c
@@ -541,7 +541,6 @@ H5HL__cache_prefix_serialize(const H5_ATTR_NDEBUG_UNUSED H5F_t *f, void *_image,
     H5HL_prfx_t *prfx = (H5HL_prfx_t *)_thing; /* Pointer to local heap prefix to query */
     H5HL_t      *heap;                         /* Pointer to the local heap */
     uint8_t     *image = (uint8_t *)_image;    /* Pointer into image buffer */
-    size_t       buf_size;                     /* expected size of the image buffer */
 
     FUNC_ENTER_PACKAGE_NOERR
 
@@ -558,11 +557,13 @@ H5HL__cache_prefix_serialize(const H5_ATTR_NDEBUG_UNUSED H5F_t *f, void *_image,
     heap = prfx->heap;
     HDassert(heap);
 
+#ifndef NDEBUG
     /* Compute the buffer size */
-    buf_size = heap->prfx_size;
+    size_t buf_size = heap->prfx_size; /* expected size of the image buffer */
     if (heap->single_cache_obj)
         buf_size += heap->dblk_size;
     HDassert(len == buf_size);
+#endif
 
     /* Update the free block value from the free list */
     heap->free_block = heap->freelist ? heap->freelist->offset : H5HL_FREE_NULL;
diff --git a/src/H5Tref.c b/src/H5Tref.c
index aea322a..f914b8d 100644
--- a/src/H5Tref.c
+++ b/src/H5Tref.c
@@ -961,13 +961,12 @@ done:
 static herr_t
 H5T__ref_disk_write(H5VL_object_t H5_ATTR_UNUSED *src_file, const void *src_buf, size_t src_size,
                     H5R_type_t H5_ATTR_UNUSED src_type, H5VL_object_t *dst_file, void *dst_buf,
-                    size_t dst_size, void *bg_buf)
+                    size_t H5_ATTR_NDEBUG_UNUSED dst_size, void *bg_buf)
 {
-    const uint8_t *p             = (const uint8_t *)src_buf;
-    uint8_t       *q             = (uint8_t *)dst_buf;
-    size_t         buf_size_left = dst_size;
-    uint8_t       *p_bg          = (uint8_t *)bg_buf;
-    herr_t         ret_value     = SUCCEED;
+    const uint8_t *p         = (const uint8_t *)src_buf;
+    uint8_t       *q         = (uint8_t *)dst_buf;
+    uint8_t       *p_bg      = (uint8_t *)bg_buf;
+    herr_t         ret_value = SUCCEED;
 
     FUNC_ENTER_PACKAGE
     H5T_REF_LOG_DEBUG("");
@@ -980,12 +979,14 @@ H5T__ref_disk_write(H5VL_object_t H5_ATTR_UNUSED *src_file, const void *src_buf,
     /* TODO Should get rid of bg stuff */
     if (p_bg) {
         H5VL_blob_specific_args_t vol_cb_args; /* Arguments to VOL callback */
-        size_t                    p_buf_size_left = dst_size;
 
         /* Skip the size / header */
         p_bg += (sizeof(uint32_t) + H5R_ENCODE_HEADER_SIZE);
+
+#ifndef NDEBUG
+        size_t p_buf_size_left = dst_size;
         HDassert(p_buf_size_left > (sizeof(uint32_t) + H5R_ENCODE_HEADER_SIZE));
-        p_buf_size_left -= (sizeof(uint32_t) + H5R_ENCODE_HEADER_SIZE);
+#endif
 
         /* Set up VOL callback arguments */
         vol_cb_args.op_type = H5VL_BLOB_DELETE;
@@ -1000,12 +1001,14 @@ H5T__ref_disk_write(H5VL_object_t H5_ATTR_UNUSED *src_file, const void *src_buf,
     p += H5R_ENCODE_HEADER_SIZE;
     q += H5R_ENCODE_HEADER_SIZE;
     src_size -= H5R_ENCODE_HEADER_SIZE;
-    buf_size_left -= sizeof(uint32_t);
+
+#ifndef NDEBUG
+    size_t buf_size_left = dst_size - sizeof(uint32_t);
+    HDassert(buf_size_left > sizeof(uint32_t));
+#endif
 
     /* Set the size */
     UINT32ENCODE(q, src_size);
-    HDassert(buf_size_left > sizeof(uint32_t));
-    buf_size_left -= sizeof(uint32_t);
 
     /* Store blob */
     if (H5VL_blob_put(dst_file, p, src_size, q, NULL) < 0)
diff --git a/src/uthash.h b/src/uthash.h
index ecf512d..b1e5cbb 100644
--- a/src/uthash.h
+++ b/src/uthash.h
@@ -699,28 +699,29 @@ typedef unsigned char uint8_t;
         hashv += (unsigned)(keylen);                                                                         \
         switch (_hj_k) {                                                                                     \
             case 11:                                                                                         \
-                hashv += ((unsigned)_hj_key[10] << 24); /* FALLTHROUGH */                                    \
-            case 10:                                                                                         \
-                hashv += ((unsigned)_hj_key[9] << 16); /* FALLTHROUGH */                                     \
-            case 9:                                                                                          \
-                hashv += ((unsigned)_hj_key[8] << 8); /* FALLTHROUGH */                                      \
-            case 8:                                                                                          \
-                _hj_j += ((unsigned)_hj_key[7] << 24); /* FALLTHROUGH */                                     \
-            case 7:                                                                                          \
-                _hj_j += ((unsigned)_hj_key[6] << 16); /* FALLTHROUGH */                                     \
-            case 6:                                                                                          \
-                _hj_j += ((unsigned)_hj_key[5] << 8); /* FALLTHROUGH */                                      \
-            case 5:                                                                                          \
-                _hj_j += _hj_key[4]; /* FALLTHROUGH */                                                       \
-            case 4:                                                                                          \
-                _hj_i += ((unsigned)_hj_key[3] << 24); /* FALLTHROUGH */                                     \
-            case 3:                                                                                          \
-                _hj_i += ((unsigned)_hj_key[2] << 16); /* FALLTHROUGH */                                     \
-            case 2:                                                                                          \
-                _hj_i += ((unsigned)_hj_key[1] << 8); /* FALLTHROUGH */                                      \
-            case 1:                                                                                          \
-                _hj_i += _hj_key[0]; /* FALLTHROUGH */                                                       \
-            default:;                                                                                        \
+                hashv += ((unsigned)_hj_key[10] << 24);                                                      \
+                H5_ATTR_FALLTHROUGH /* FALLTHROUGH */                                                        \
+                    case 10 : hashv += ((unsigned)_hj_key[9] << 16);                                         \
+                H5_ATTR_FALLTHROUGH /* FALLTHROUGH */                                                        \
+                    case 9 : hashv += ((unsigned)_hj_key[8] << 8);                                           \
+                H5_ATTR_FALLTHROUGH /* FALLTHROUGH */                                                        \
+                    case 8 : _hj_j += ((unsigned)_hj_key[7] << 24);                                          \
+                H5_ATTR_FALLTHROUGH /* FALLTHROUGH */                                                        \
+                    case 7 : _hj_j += ((unsigned)_hj_key[6] << 16);                                          \
+                H5_ATTR_FALLTHROUGH /* FALLTHROUGH */                                                        \
+                    case 6 : _hj_j += ((unsigned)_hj_key[5] << 8);                                           \
+                H5_ATTR_FALLTHROUGH /* FALLTHROUGH */                                                        \
+                    case 5 : _hj_j += _hj_key[4];                                                            \
+                H5_ATTR_FALLTHROUGH /* FALLTHROUGH */                                                        \
+                    case 4 : _hj_i += ((unsigned)_hj_key[3] << 24);                                          \
+                H5_ATTR_FALLTHROUGH /* FALLTHROUGH */                                                        \
+                    case 3 : _hj_i += ((unsigned)_hj_key[2] << 16);                                          \
+                H5_ATTR_FALLTHROUGH /* FALLTHROUGH */                                                        \
+                    case 2 : _hj_i += ((unsigned)_hj_key[1] << 8);                                           \
+                H5_ATTR_FALLTHROUGH /* FALLTHROUGH */                                                        \
+                    case 1 : _hj_i += _hj_key[0];                                                            \
+                H5_ATTR_FALLTHROUGH /* FALLTHROUGH */                                                        \
+                    default:;                                                                                \
         }                                                                                                    \
         HASH_JEN_MIX(_hj_i, _hj_j, hashv);                                                                   \
     } while (0)
diff --git a/test/objcopy.c b/test/objcopy.c
index b0050f7..beb272b 100644
--- a/test/objcopy.c
+++ b/test/objcopy.c
@@ -1678,11 +1678,17 @@ compare_groups(hid_t gid, hid_t gid2, hid_t pid, int depth, unsigned copy_flags)
                     case H5O_TYPE_MAP:
                         HDassert(0 && "maps not supported in native VOL connector");
 
+                        /* clang complains about implicit fallthrough here and
+                         * our usual attributes and fall-through comments don't
+                         * quiet the compiler.
+                         */
+                        H5_CLANG_DIAG_OFF("implicit-fallthrough")
                     case H5O_TYPE_UNKNOWN:
                     case H5O_TYPE_NTYPES:
                     default:
                         HDassert(0 && "Unknown type of object");
                         break;
+                        H5_CLANG_DIAG_ON("implicit-fallthrough")
                 } /* end switch */
 
                 /* Close objects */
diff --git a/test/objcopy_ref.c b/test/objcopy_ref.c
index bee722a..12dc836 100644
--- a/test/objcopy_ref.c
+++ b/test/objcopy_ref.c
@@ -1390,11 +1390,17 @@ compare_groups(hid_t gid, hid_t gid2, hid_t pid, int depth, unsigned copy_flags)
                     case H5O_TYPE_MAP:
                         HDassert(0 && "maps not supported in native VOL connector");
 
+                        /* clang complains about implicit fallthrough here and
+                         * our usual attributes and fall-through comments don't
+                         * quiet the compiler.
+                         */
+                        H5_CLANG_DIAG_OFF("implicit-fallthrough")
                     case H5O_TYPE_UNKNOWN:
                     case H5O_TYPE_NTYPES:
                     default:
                         HDassert(0 && "Unknown type of object");
                         break;
+                        H5_CLANG_DIAG_ON("implicit-fallthrough")
                 } /* end switch */
 
                 /* Close objects */