make: avoided the warning message when do make.

change: code style, delete some useless spaces(visual code).

eg:

warning: ignoring return value of ‘asprintf’, declared with attribute warn_unused_result

src/gvc.c

@@ -24,9 +24,11 @@ void r3_tree_build_ag_nodes(Agraph_t * g, Agnode_t * ag_parent_node, const node
 
         char *nodename = NULL;
         if ( e && e->child && e->child->combined_pattern ) {
-            asprintf(&nodename,"%s", e->child->combined_pattern);
+            int r = asprintf(&nodename,"%s", e->child->combined_pattern);
+            if (r) {};
         } else {
-            asprintf(&nodename,"#%d", *node_cnt);
+            int r = asprintf(&nodename,"#%d", *node_cnt);
+            if (r) {};
         }
 
         agn_child = agnode(g, nodename, 1);

src/node.c

@@ -173,7 +173,8 @@ int r3_tree_compile_patterns(R3Node * n, char **errstr) {
     char * p;
     char * cpat = calloc(1, sizeof(char) * 64 * 3); // XXX
     if (!cpat) {
-        asprintf(errstr, "Can not allocate memory");
+        int r = asprintf(errstr, "Can not allocate memory");
+        if (r) {};
         return -1;
     }
 
@@ -239,7 +240,8 @@ int r3_tree_compile_patterns(R3Node * n, char **errstr) {
             NULL);                /* use default character tables */
     if (n->pcre_pattern == NULL) {
         if (errstr) {
-            asprintf(errstr, "PCRE compilation failed at offset %d: %s, pattern: %s", pcre_erroffset, pcre_error, n->combined_pattern);
+            int r = asprintf(errstr, "PCRE compilation failed at offset %d: %s, pattern: %s", pcre_erroffset, pcre_error, n->combined_pattern);
+            if (r) {};
         }
         return -1;
     }
@@ -250,7 +252,8 @@ int r3_tree_compile_patterns(R3Node * n, char **errstr) {
     n->pcre_extra = pcre_study(n->pcre_pattern, 0, &pcre_error);
     if (!n->pcre_extra) {
         if (errstr) {
-            asprintf(errstr, "PCRE study failed at offset %s, pattern: %s", pcre_error, n->combined_pattern);
+            int r = asprintf(errstr, "PCRE study failed at offset %s, pattern: %s", pcre_error, n->combined_pattern);
+            if (r) {};
         }
         return -1;
     }

src/slug.c

@@ -60,7 +60,8 @@ int r3_slug_check(r3_slug_t *s) {
 
 char * r3_slug_to_str(const r3_slug_t *s) {
     char *str = NULL;
-    asprintf(&str, "slug: '%.*s', pattern: '%.*s', path: '%.*s'", s->len, s->begin, s->pattern_len, s->pattern, s->path_len, s->path);
+    int r = asprintf(&str, "slug: '%.*s', pattern: '%.*s', path: '%.*s'", s->len, s->begin, s->pattern_len, s->pattern, s->path_len, s->path);
+    if (r) {};
     return str;
 }
 
@@ -139,7 +140,8 @@ int r3_slug_parse(r3_slug_t *s, const char *needle, int needle_len, const char *
     if (state != 0) {
         if (errstr) {
             char *err = NULL;
-            asprintf(&err, "Incomplete slug pattern. PATH (%d): '%s', OFFSET: %ld, STATE: %d", needle_len, needle, p - needle, state);
+            int r = asprintf(&err, "Incomplete slug pattern. PATH (%d): '%s', OFFSET: %ld, STATE: %d", needle_len, needle, p - needle, state);
+            if (r) {};
             *errstr = err;
         }
         return -1;
@@ -177,7 +179,8 @@ int r3_slug_count(const char * needle, int len, char **errstr) {
     if (state != 0) {
         if (errstr) {
             char *err = NULL;
-            asprintf(&err, "Incomplete slug pattern. PATTERN (%d): '%s', OFFSET: %ld, STATE: %d", len, needle, p - needle, state);
+            int r = asprintf(&err, "Incomplete slug pattern. PATTERN (%d): '%s', OFFSET: %ld, STATE: %d", len, needle, p - needle, state);
+            if (r) {};
             *errstr = err;
         }
         return -1;

src/str.c

@@ -78,7 +78,8 @@ char * r3_inside_slug(const char * needle, int needle_len, char *offset, char **
     if (found_s1 || found_s2) {
         // wrong slug pattern
         if(errstr) {
-            asprintf(errstr, "Incomplete slug pattern");
+            int r = asprintf(errstr, "Incomplete slug pattern");
+            if (r) {};
         }
         return NULL;
     }