diff --git a/tools/ctf/cvt/ctf.c b/tools/ctf/cvt/ctf.c
index 1e425758c249..83f09cb43e6e 100644
--- a/tools/ctf/cvt/ctf.c
+++ b/tools/ctf/cvt/ctf.c
@@ -1216,7 +1216,7 @@ decompress_ctf(caddr_t cbuf, size_t cbufsz, caddr_t dbuf, size_t dbufsz)
 	    (rc = inflate(&zstr, Z_NO_FLUSH)) != Z_STREAM_END ||
 	    (rc = inflateEnd(&zstr)) != Z_OK) {
 		warning("CTF decompress zlib error %s\n", zError(rc));
-		return (NULL);
+		return (0);
 	}
 
 	debug(3, "reflated %lu bytes to %lu, pointer at %d\n",
diff --git a/tools/ctf/cvt/dwarf.c b/tools/ctf/cvt/dwarf.c
index e261818d3a66..5fdcd35e33da 100644
--- a/tools/ctf/cvt/dwarf.c
+++ b/tools/ctf/cvt/dwarf.c
@@ -1714,7 +1714,7 @@ static const die_creator_t die_creators[] = {
 	{ DW_TAG_variable,		DW_F_NOTDP,	die_variable_create },
 	{ DW_TAG_volatile_type,		0,		die_volatile_create },
 	{ DW_TAG_restrict_type,		0,		die_restrict_create },
-	{ 0, NULL }
+	{ 0, 0, NULL }
 };
 
 static const die_creator_t *
diff --git a/tools/ctf/cvt/output.c b/tools/ctf/cvt/output.c
index f699fbf6d30f..90c87dabf331 100644
--- a/tools/ctf/cvt/output.c
+++ b/tools/ctf/cvt/output.c
@@ -23,8 +23,6 @@
  * Use is subject to license terms.
  */
 
-#pragma ident	"%Z%%M%	%I%	%E% SMI"
-
 /*
  * Routines for preparing tdata trees for conversion into CTF data, and
  * for placing the resulting data into an output file.
@@ -466,7 +464,7 @@ write_file(Elf *src, const char *srcname, Elf *dst, const char *dstname,
 	int pad;
 	int i;
 
-	if (gelf_newehdr(dst, gelf_getclass(src)) == NULL)
+	if (gelf_newehdr(dst, gelf_getclass(src)) == 0)
 		elfterminate(dstname, "Cannot copy ehdr to temp file");
 	gelf_getehdr(src, &sehdr);
 	memcpy(&dehdr, &sehdr, sizeof (GElf_Ehdr));
@@ -482,7 +480,7 @@ write_file(Elf *src, const char *srcname, Elf *dst, const char *dstname,
 	 */
 	if (sehdr.e_phnum != 0) {
 		(void) elf_flagelf(dst, ELF_C_SET, ELF_F_LAYOUT);
-		if (gelf_newphdr(dst, sehdr.e_phnum) == NULL)
+		if (gelf_newphdr(dst, sehdr.e_phnum) == 0)
 			elfterminate(dstname, "Cannot make phdrs in temp file");
 
 		for (i = 0; i < sehdr.e_phnum; i++) {
@@ -616,7 +614,7 @@ write_file(Elf *src, const char *srcname, Elf *dst, const char *dstname,
 			}
 		}
 
-		if (gelf_update_shdr(dscn, &shdr) == NULL)
+		if (gelf_update_shdr(dscn, &shdr) == 0)
 			elfterminate(dstname, "Cannot update sect %s", sname);
 
 		new_offset = (off_t)shdr.sh_offset;