Many fixes to various compiler warnings (#3124)

* Fixed various -Wmissing-variable-declarations by adding static keyword
* In a few cases, renamed the variable suffix from _g to _s.
* Fixed some -Wmissing-variable-declarations by using different declaration macros
* Fixed various -Wconditional-uninitialized warnings by just initializing variable to zero
* Fixed various -Wcomma warnings
* Fixed clang -Wstrict-prototypes warnings
* Fixed various -Wunused-variable warnings
* Updated some casts to fix the only 3 -Wcast-qual warnings
* Fixed the only -Wsometimes-uninitialized warning

8 files changed, 22 insertions, 21 deletions

diff --git a/hl/examples/ex_image1.c b/hl/examples/ex_image1.c
index d9080cb..49a9093 100644
--- a/hl/examples/ex_image1.c
+++ b/hl/examples/ex_image1.c
@@ -16,7 +16,7 @@
 #define WIDTH       400
 #define HEIGHT      200
 #define PAL_ENTRIES 9
-unsigned char buf[WIDTH * HEIGHT];
+static unsigned char buf[WIDTH * HEIGHT];
 
 int
 main(void)
diff --git a/hl/examples/ex_image2.c b/hl/examples/ex_image2.c
index 579b126..9ce1746 100644
--- a/hl/examples/ex_image2.c
+++ b/hl/examples/ex_image2.c
@@ -22,8 +22,8 @@
 #define PAL_NAME    "palette"
 #define PAL_ENTRIES 256
 
-static int     read_data(const char *file_name, hsize_t *width, hsize_t *height);
-unsigned char *gbuf = NULL; /* global buffer for image data */
+static int            read_data(const char *file_name, hsize_t *width, hsize_t *height);
+static unsigned char *gbuf = NULL; /* global buffer for image data */
 
 int
 main(void)
diff --git a/hl/src/H5DS.c b/hl/src/H5DS.c
index 87973fa..c576573 100644
--- a/hl/src/H5DS.c
+++ b/hl/src/H5DS.c
@@ -152,14 +152,14 @@ H5DSattach_scale(hid_t did, hid_t dsid, unsigned int idx)
     ds_list_t *dsbuf = NULL; /* array of attribute data in the DS pointing to the dataset */
     ds_list_t *dsbuf_w =
         NULL; /* array of "REFERENCE_LIST" attribute data to write when adding new reference to a dataset */
-    hobj_ref_t ref_to_ds; /* reference to the DS */
-    hobj_ref_t ref_j;     /* iterator reference */
+    hobj_ref_t ref_to_ds = HADDR_UNDEF; /* reference to the DS */
+    hobj_ref_t ref_j;                   /* iterator reference */
 
     /* Variables to be used when new references are used */
     nds_list_t  ndsl;
-    nds_list_t *ndsbuf   = NULL;
-    nds_list_t *ndsbuf_w = NULL;
-    H5R_ref_t   nref_to_ds;
+    nds_list_t *ndsbuf     = NULL;
+    nds_list_t *ndsbuf_w   = NULL;
+    H5R_ref_t   nref_to_ds = {0};
     H5R_ref_t   nref_j;
     hbool_t     is_new_ref;
 
diff --git a/hl/test/test_ld.c b/hl/test/test_ld.c
index b056225..78af519 100644
--- a/hl/test/test_ld.c
+++ b/hl/test/test_ld.c
@@ -52,7 +52,7 @@
  *    Varies from 10->13; 10->9, 10->10, 10->1, 10->11
  */
 #define ONE_NTESTS 5
-int one_tests[ONE_NTESTS] = {3, -1, 0, -9, 1};
+static int one_tests[ONE_NTESTS] = {3, -1, 0, -9, 1};
 
 /*
  * Test variations (retained original) for two-dimensional dataset:
@@ -61,7 +61,8 @@ int one_tests[ONE_NTESTS] = {3, -1, 0, -9, 1};
  *            {4,10}->{4,12}; {4,10}->{4,9}; {4,10}->{4,10}
  */
 #define TWO_NTESTS 9
-int two_tests[TWO_NTESTS][2] = {{2, 2}, {2, -1}, {2, 0}, {-1, 2}, {-1, -1}, {-1, 0}, {0, 2}, {0, -1}, {0, 0}};
+static int two_tests[TWO_NTESTS][2] = {{2, 2},  {2, -1}, {2, 0},  {-1, 2}, {-1, -1},
+                                       {-1, 0}, {0, 2},  {0, -1}, {0, 0}};
 
 /* Verify that the two input values are the same */
 #define VERIFY_EQUAL(_x, _y)                                                                                 \
@@ -210,12 +211,12 @@ typedef struct test_valid_fields2 {
 
 /* Temporary buffers for tests: test_LD_elmts_one() & test_LD_elmts_two() */
 #define TEST_BUF_SIZE 100
-int                *iibuf; /* buffer for storing retrieved elements */
-int                *ibuf;  /* buffer for storing retrieved elements (integer) */
-set_t              *cbuf;  /* buffer for storing retrieved elements (compound) */
-set_t              *ccbuf; /* buffer for storing retrieved elements (compound) */
-test_valid_fields1 *vbuf1; /* buffer for storing retrieved elements (FIELDS1) */
-test_valid_fields2 *vbuf2; /* buffer for storing retrieved elements (FIELDS2) */
+static int                *iibuf; /* buffer for storing retrieved elements */
+static int                *ibuf;  /* buffer for storing retrieved elements (integer) */
+static set_t              *cbuf;  /* buffer for storing retrieved elements (compound) */
+static set_t              *ccbuf; /* buffer for storing retrieved elements (compound) */
+static test_valid_fields1 *vbuf1; /* buffer for storing retrieved elements (FIELDS1) */
+static test_valid_fields2 *vbuf2; /* buffer for storing retrieved elements (FIELDS2) */
 
 /*
  *********************************************************************************
diff --git a/hl/test/test_packet_vlen.c b/hl/test/test_packet_vlen.c
index 5e06c85..1d6195d 100644
--- a/hl/test/test_packet_vlen.c
+++ b/hl/test/test_packet_vlen.c
@@ -763,7 +763,7 @@ error: /* An error has occurred.  Clean up and exit. */
  */
 #define ATTR_RANK 1
 #define ATTR_DIM  3
-int attr_data[ATTR_DIM] = {256, 11945, -22107}; /* values to be written to attr */
+static int attr_data[ATTR_DIM] = {256, 11945, -22107}; /* values to be written to attr */
 
 static int
 adding_attribute(hid_t fid, const char *table_name, const char *attr_name)
diff --git a/hl/tools/gif2h5/decompress.c b/hl/tools/gif2h5/decompress.c
index dabadf5..e87a60c 100644
--- a/hl/tools/gif2h5/decompress.c
+++ b/hl/tools/gif2h5/decompress.c
@@ -54,8 +54,8 @@ GIFBYTE *Raster; /* The raster data stream, unblocked            */
 
 /* The hash table used by the decompressor */
 
-int *Prefix;
-int *Suffix;
+static int *Prefix;
+static int *Suffix;
 
 /* An output array used by the decompressor */
 
diff --git a/hl/tools/gif2h5/hdf2gif.c b/hl/tools/gif2h5/hdf2gif.c
index 2fd9756..8805c80 100644
--- a/hl/tools/gif2h5/hdf2gif.c
+++ b/hl/tools/gif2h5/hdf2gif.c
@@ -49,7 +49,7 @@ leave(int ret)
     HDexit(ret);
 }
 
-FILE *fpGif = NULL;
+static FILE *fpGif = NULL;
 int
 main(int argc, char **argv)
 {
diff --git a/hl/tools/h5watch/h5watch.c b/hl/tools/h5watch/h5watch.c
index 248fb90..102ff93 100644
--- a/hl/tools/h5watch/h5watch.c
+++ b/hl/tools/h5watch/h5watch.c
@@ -27,7 +27,7 @@
  *    This tool uses H5LD_memb_t data structure declared in H5LDprivate.h
  */
 
-const char          *progname         = "h5watch"; /* tool name */
+static const char   *progname         = "h5watch"; /* tool name */
 static char         *g_list_of_fields = NULL;      /* command line input for "list_of_fields" */
 static char         *g_dup_fields     = NULL;      /* copy of "list_of_fields" */
 static H5LD_memb_t **g_listv          = NULL;      /* vector info for "list_of_fields" */