diff --git a/CHANGELOG.md b/CHANGELOG.md
index 2cb7ab13..d8192326 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -96,6 +96,7 @@ Users may have to change how they access the system
 
 ### Minor features
 
+* Removed ifdef __GNUC__ around printf-like prototypes since both clang and gcc have format/printf macros defined
 * Test changes
   * Use `YANG_STANDARD_DIR` from `./configure --with-yang-standard-dir=DIR` instead of `YANGMODELS` from site.sh
   * Remove dependency of IETF YANGs on most tests
diff --git a/apps/restconf/restconf_api.h b/apps/restconf/restconf_api.h
index a44cb440..947847aa 100644
--- a/apps/restconf/restconf_api.h
+++ b/apps/restconf/restconf_api.h
@@ -41,11 +41,7 @@
 /*
  * Prototypes
  */
-#if defined(__GNUC__) && __GNUC__ >= 3
 int restconf_reply_header(void *req, const char *name, const char *vfmt, ...)  __attribute__ ((format (printf, 3, 4)));
-#else
-int restconf_reply_header(void *req, const char *name, const char *vfmt, ...);
-#endif
 
 /* note cb is consumed dont free */
 int restconf_reply_send(void *req, int code, cbuf *cb, int head);
diff --git a/lib/clixon/clixon_err.h b/lib/clixon/clixon_err.h
index e21c8bfb..b108469c 100644
--- a/lib/clixon/clixon_err.h
+++ b/lib/clixon/clixon_err.h
@@ -105,11 +105,7 @@ extern char clicon_err_reason[ERR_STRLEN];
  * Prototypes
  */
 int   clicon_err_reset(void);
-#if defined(__GNUC__) && __GNUC__ >= 3
 int   clicon_err_fn(const char *fn, const int line, int category, int err, const char *format, ...) __attribute__ ((format (printf, 5, 6)));
-#else
-int   clicon_err_fn(const char *fn, const int line, int category, int err, const char *format, ...);
-#endif
 char *clicon_strerror(int err);
 void *clicon_err_save(void);
 int   clicon_err_restore(void *handle);
diff --git a/lib/clixon/clixon_log.h b/lib/clixon/clixon_log.h
index f260648f..74b760b9 100644
--- a/lib/clixon/clixon_log.h
+++ b/lib/clixon/clixon_log.h
@@ -56,13 +56,8 @@ int clicon_log_exit(void);
 int clicon_log_opt(char c);
 int clicon_log_file(char *filename);
 int clicon_get_logflags(void);
-#if defined(__GNUC__) && __GNUC__ >= 3
 int clicon_log(int level, const char *format, ...) __attribute__ ((format (printf, 2, 3)));
 int clicon_debug(int dbglevel, const char *format, ...) __attribute__ ((format (printf, 2, 3)));
-#else
-int clicon_log(int level, const char *format, ...);
-int clicon_debug(int dbglevel, const char *format, ...);
-#endif
 int clicon_debug_init(int dbglevel, FILE *f);
 int clicon_debug_get(void);
 
diff --git a/lib/clixon/clixon_path.h b/lib/clixon/clixon_path.h
index 6baa2b6c..82d5e3ab 100644
--- a/lib/clixon/clixon_path.h
+++ b/lib/clixon/clixon_path.h
@@ -85,18 +85,11 @@ int api_path2xml(char *api_path, yang_stmt *yspec, cxobj *xtop,
 		 yang_class nodeclass, int strict,
 		 cxobj **xpathp, yang_stmt **ypathp, cxobj **xerr);
 int xml2api_path_1(cxobj *x, cbuf *cb);
-#if defined(__GNUC__) && __GNUC__ >= 3
 int clixon_xml_find_api_path(cxobj *xt, yang_stmt *yt, cxobj ***xvec, int *xlen, const char *format,
 		     ...) __attribute__ ((format (printf, 5, 6)));;
 int clixon_xml_find_instance_id(cxobj *xt, yang_stmt *yt, cxobj ***xvec, int *xlen, const char *format,
 		     ...) __attribute__ ((format (printf, 5, 6)));;
 int clixon_instance_id_bind(yang_stmt *yt, cvec *nsctx, const char *format, ...) __attribute__ ((format (printf, 3, 4)));
 int clixon_instance_id_parse(yang_stmt *yt, clixon_path **cplistp, cxobj **xerr, const char *format, ...) __attribute__ ((format (printf, 4, 5)));
-#else
-int clixon_xml_find_api_path(cxobj *xt, yang_stmt *yt,  cxobj ***xvec, int *xlen, const char *format, ...);
-int clixon_xml_find_instance_id(cxobj *xt, yang_stmt *yt, cxobj ***xvec, int *xlen, const char *format, ...);
-int clixon_instance_id_bind(yang_stmt *yt, cvec *nsctx, const char *format, ...);
-int clixon_instance_id_parse(yang_stmt *yt, clixon_path **cplistp, cxobj **xerr, const char *format, ...);
-#endif
 
 #endif  /* _CLIXON_PATH_H_ */
diff --git a/lib/clixon/clixon_proto.h b/lib/clixon/clixon_proto.h
index ef0fc872..39357f64 100644
--- a/lib/clixon/clixon_proto.h
+++ b/lib/clixon/clixon_proto.h
@@ -64,11 +64,7 @@ struct clicon_msg {
 char *format_int2str(enum format_enum showas);
 enum format_enum format_str2int(char *str);
 
-#if defined(__GNUC__) && __GNUC__ >= 3
 struct clicon_msg *clicon_msg_encode(uint32_t id, const char *format, ...) __attribute__ ((format (printf, 2, 3)));
-#else
-struct clicon_msg *clicon_msg_encode(uint32_t id, const char *format, ...);
-#endif
 int clicon_msg_decode(struct clicon_msg *msg, yang_stmt *yspec, uint32_t *id, cxobj **xml, cxobj **xerr);
 
 int clicon_connect_unix(clicon_handle h, char *sockpath);
diff --git a/lib/clixon/clixon_stream.h b/lib/clixon/clixon_stream.h
index c5be0f36..8dd26523 100644
--- a/lib/clixon/clixon_stream.h
+++ b/lib/clixon/clixon_stream.h
@@ -120,11 +120,7 @@ int stream_ss_delete_all(clicon_handle h, stream_fn_t fn, void *arg);
 int stream_ss_delete(clicon_handle h, char *name, stream_fn_t fn, void *arg);
 
 int stream_notify_xml(clicon_handle h, char *stream, cxobj *xml);
-#if defined(__GNUC__) && __GNUC__ >= 3
 int stream_notify(clicon_handle h, char *stream, const char *event, ...)  __attribute__ ((format (printf, 3, 4)));
-#else
-int stream_notify(clicon_handle h, char *stream, const char *event, ...);
-#endif
 
 /* Replay */
 int stream_replay_add(event_stream_t *es, struct timeval *tv, cxobj *xv);
diff --git a/lib/clixon/clixon_string.h b/lib/clixon/clixon_string.h
index e1427863..bffa5a37 100644
--- a/lib/clixon/clixon_string.h
+++ b/lib/clixon/clixon_string.h
@@ -91,13 +91,8 @@ char **clicon_strsep(char *string, char *delim, int  *nvec0);
 char  *clicon_strjoin (int argc, char **argv, char *delim);
 int    clixon_strsplit(char *nodeid, const int delim, char **prefix, char **id);
 int    uri_str2cvec(char *string, char delim1, char delim2, int decode, cvec **cvp);
-#if defined(__GNUC__) && __GNUC__ >= 3
 int    uri_percent_encode(char **encp, const char *fmt, ...) __attribute__ ((format (printf, 2, 3)));
 int    xml_chardata_encode(char **escp, const char *fmt, ... ) __attribute__ ((format (printf, 2, 3)));
-#else
-int    uri_percent_encode(char **encp, const char *str, ...);
-int    xml_chardata_encode(char **escp, const char *fmt, ...);
-#endif
 int    xml_chardata_cbuf_append(cbuf *cb, char *str);
 int    uri_percent_decode(char *enc, char **str);
 
diff --git a/lib/clixon/clixon_xml.h b/lib/clixon/clixon_xml.h
index f77a5690..7c884c98 100644
--- a/lib/clixon/clixon_xml.h
+++ b/lib/clixon/clixon_xml.h
@@ -272,11 +272,7 @@ cxobj    *xml_root(cxobj *xn);
 int       xml_operation(char *opstr, enum operation_type *op);
 char     *xml_operation2str(enum operation_type op);
 int       xml_attr_insert2val(char *instr, enum insert_type *ins);
-#if defined(__GNUC__) && __GNUC__ >= 3
 int       clicon_log_xml(int level, cxobj *x, const char *format, ...)  __attribute__ ((format (printf, 3, 4)));
-#else
-int       clicon_log_xml(int level, cxobj *x, const char *format, ...);
-#endif
 #ifdef XML_EXPLICIT_INDEX
 int       xml_search_index_p(cxobj *x);
 
diff --git a/lib/clixon/clixon_xml_io.h b/lib/clixon/clixon_xml_io.h
index 83ead228..33c92ac2 100644
--- a/lib/clixon/clixon_xml_io.h
+++ b/lib/clixon/clixon_xml_io.h
@@ -53,14 +53,8 @@ int xmltree2cbuf(cbuf *cb, cxobj *x, int level);
 
 int clixon_xml_parse_file(FILE *f, yang_bind yb, yang_stmt *yspec, cxobj **xt, cxobj **xerr);
 int clixon_xml_parse_string(const char *str, yang_bind yb, yang_stmt *yspec, cxobj **xt, cxobj **xerr);
-
-#if defined(__GNUC__) && __GNUC__ >= 3
 int clixon_xml_parse_va(yang_bind yb, yang_stmt *yspec, cxobj **xt, cxobj **xerr, 
 			const char *format, ...)  __attribute__ ((format (printf, 5, 6)));
-#else
-int clixon_xml_parse_va(yang_bind yb, yang_stmt *yspec, cxobj **xt, cxobj **xerr,
-			const char *format, ...);
-#endif
 int clixon_xml_attr_copy(cxobj *xin, cxobj *xout, char *name);
 
 #endif	/* _CLIXON_XML_IO_H_ */
diff --git a/lib/clixon/clixon_xpath.h b/lib/clixon/clixon_xpath.h
index e7ee1414..cef1c0e7 100644
--- a/lib/clixon/clixon_xpath.h
+++ b/lib/clixon/clixon_xpath.h
@@ -134,31 +134,18 @@ int   xpath_tree_free(xpath_tree *xs);
 int   xpath_parse(const char *xpath, xpath_tree **xptree);
 int   xpath_vec_ctx(cxobj *xcur, cvec *nsc, const char *xpath, int localonly, xp_ctx  **xrp);
 
-#if defined(__GNUC__) && __GNUC__ >= 3
 int    xpath_vec_bool(cxobj *xcur, cvec *nsc, const char *xpformat, ...) __attribute__ ((format (printf, 3, 4)));
 int    xpath_vec_flag(cxobj *xcur, cvec *nsc, const char *xpformat, uint16_t flags, 
 		   cxobj ***vec, int *veclen, ...) __attribute__ ((format (printf, 3, 7)));
 
-#else
-int    xpath_vec_bool(cxobj *xcur, cvec *nsc, const char *xpformat, ...);
-int    xpath_vec_flag(cxobj *xcur, cvec *nsc, const char *xpformat, uint16_t flags, 
-		      cxobj ***vec, int *veclen, ...);
-#endif
-
 /* Functions with explicit namespace context (nsc) set. If you do not need 
  * explicit namespace contexts (most do not) consider using the API functions
  * below without nsc set.
  * If you do not know what a namespace context is, see README.md#xml-and-xpath
  */
-#if defined(__GNUC__) && __GNUC__ >= 3
 cxobj *xpath_first(cxobj *xcur, cvec *nsc, const char *xpformat,  ...) __attribute__ ((format (printf, 3, 4)));
 cxobj *xpath_first_localonly(cxobj *xcur, const char *xpformat,  ...) __attribute__ ((format (printf, 2, 3)));
 int    xpath_vec(cxobj *xcur, cvec *nsc, const char *xpformat, cxobj ***vec, size_t *veclen, ...) __attribute__ ((format (printf, 3, 6)));
-#else
-cxobj *xpath_first(cxobj *xcur, cvec *nsc, const char *xpformat, ...);
-cxobj *xpath_first_localonly(cxobj *xcur, const char *xpformat, ...);
-int    xpath_vec(cxobj *xcur, cvec *nsc, const char *xpformat, cxobj  ***vec, size_t *veclen, ...);
-#endif
 
 int xpath2canonical(const char *xpath0, cvec *nsc0, yang_stmt *yspec, char **xpath1, cvec **nsc1, cbuf **cbreason);
 int xpath_count(cxobj *xcur, cvec *nsc, const char *xpath, uint32_t *count);