strlist, warnings: improve strlist, buffer warnings until error

Make strlist_free() take a pointer to a pointer, so we can set it to
NULL.

Buffer warnings on a strlist until we either get an error or we are in
pass 2. Hopefully this should let us get rid of a lot of the ERR_PASS*
bullshit, which far too often causes messages to get lost.

asm/labels.c contains one example of a warning that cannot be made
correct with a specific pass number.

Signed-off-by: H. Peter Anvin (Intel) <hpa@zytor.com>

asm/labels.c

@@ -511,9 +511,9 @@ void define_label(const char *label, int32_t segment,
              *!  value is identical. It is an unconditional error to
              *!  define the same label more than once to \e{different} values.
              */
-            nasm_warnf(WARN_LABEL_REDEF|ERR_PASS2,
+            nasm_warnf(WARN_LABEL_REDEF,
                        "label `%s' redefined to an identical value", lptr->defn.label);
-            noteflags = ERR_NOTE|ERR_HERE|WARN_LABEL_REDEF|ERR_PASS2;
+            noteflags = ERR_NOTE|ERR_HERE|WARN_LABEL_REDEF;
         }
 
         src_get(&saved_line, &saved_fname);

asm/listing.c

@@ -126,8 +126,7 @@ static void list_emit(void)
             fprintf(listfp, "  %s\n", e->str);
         }
 
-        strlist_free(list_errors);
-        list_errors = NULL;
+        strlist_free(&list_errors);
     }
 }
 

asm/nasm.c

@@ -90,6 +90,7 @@ struct error_format {
 static const struct error_format errfmt_gnu  = { ":", "",  ": "  };
 static const struct error_format errfmt_msvc = { "(", ")", " : " };
 static const struct error_format *errfmt = &errfmt_gnu;
+static struct strlist *warn_list;
 
 static bool using_debug_info, opt_verbose_info;
 static const char *debug_format;
@@ -388,7 +389,7 @@ static void emit_dependencies(struct strlist *list)
         }
     }
 
-    strlist_free(list);
+    strlist_free(&list);
 
     if (deps != stdout)
         fclose(deps);
@@ -635,7 +636,7 @@ int main(int argc, char **argv)
     eval_cleanup();
     stdscan_cleanup();
     src_free();
-    strlist_free(include_path);
+    strlist_free(&include_path);
 
     return terminate_after_phase;
 }
@@ -1117,6 +1118,7 @@ static bool process_arg(char *p, char *q, int pass)
                     break;
                 }
 
+                olen = 0;       /* Placates gcc at lower optimization levels */
                 plen = strlen(p);
                 for (tx = textopts; tx->label; tx++) {
                     olen = strlen(tx->label);
@@ -1426,6 +1428,18 @@ static void assemble_file(const char *fname, struct strlist *depend_list)
         pass2 = passn > 1  ? 2 : 1;     /* 1, 2, 2, ..., 2, 2 */
         /* pass0                           0, 0, 0, ..., 1, 2 */
 
+	/*
+	 * Create a warning buffer list unless we are in pass 2 (everything will be
+	 * emitted immediately in pass 2.)
+	 */
+	if (warn_list) {
+            if (warn_list->nstr || pass0 == 2)
+                strlist_free(&warn_list);
+	}
+
+	if (pass0 < 2 && !warn_list)
+		warn_list = strlist_alloc(false);
+
         globalbits = cmd_sb;  /* set 'bits' to command line default */
         cpu = cmd_cpu;
         if (pass0 == 2) {
@@ -1691,8 +1705,10 @@ static void assemble_file(const char *fname, struct strlist *depend_list)
         }
     }
 
+    strlist_free(&warn_list);
     preproc->cleanup(0);
     lfmt->cleanup();
+
     if (!terminate_after_phase && opt_verbose_info) {
         /*  -On and -Ov switches */
         fprintf(stdout, "info: assembly required 1+%"PRId64"+1 passes\n",
@@ -1844,10 +1860,29 @@ static void nasm_verror_asm(errflags severity, const char *fmt, va_list args)
     }
 
     if (!skip_this_pass(severity)) {
-        fprintf(error_file, "%s%s%s%s%s%s%s\n",
-                currentfile ? currentfile : "nasm",
-                linestr, errfmt->beforemsg, pfx, msg,
-                (severity & ERR_HERE) ? " here" : "", warnsuf);
+	    const char *file = currentfile ? currentfile : "nasm";
+	    const char *here = (severity & ERR_HERE) ? " here" : "";
+
+	    if (warn_list && true_type < ERR_NONFATAL) {
+		    /*
+		     * Buffer up warnings until we either get an error
+		     * or we are on the code-generation pass.
+		     */
+		    strlist_printf(warn_list, "%s%s%s%s%s%s%s",
+				   file, linestr, errfmt->beforemsg,
+				   pfx, msg, here, warnsuf);
+	    } else {
+		    /* If we have buffered warnings, output them now. */
+		    if (warn_list) {
+			    strlist_write(warn_list, "\n", error_file);
+			    strlist_free(&warn_list);
+		    }
+
+		    fprintf(error_file, "%s%s%s%s%s%s%s\n",
+			    file, linestr, errfmt->beforemsg,
+			    pfx, msg, here, warnsuf);
+
+	    }
     }
 
     /* Are we recursing from error_list_macros? */

include/strlist.h

@@ -71,7 +71,6 @@ static inline size_t strlist_size(const struct strlist *list)
 }
 
 struct strlist safe_alloc *strlist_alloc(bool uniq);
-void strlist_free(struct strlist *list);
 const struct strlist_entry * never_null strlist_add(struct strlist *list, const char *str);
 const struct strlist_entry * printf_func(2, 3) never_null
 	strlist_printf(struct strlist *list, const char *fmt, ...);
@@ -80,7 +79,8 @@ const struct strlist_entry * never_null
 const struct strlist_entry *
 strlist_find(const struct strlist *list, const char *str);
 void * safe_alloc strlist_linearize(const struct strlist *list, char sep);
-void strlist_free(struct strlist *list);
+void strlist_write(const struct strlist *list, const char *sep, FILE *f);
+void strlist_free(struct strlist **listp);
 #define strlist_for_each(p,h) list_for_each((p), strlist_head(h))
  
 #endif /* NASM_STRLIST_H */

nasmlib/strlist.c

@@ -136,21 +136,24 @@ strlist_printf(struct strlist *list, const char *fmt, ...)
 }
 
 /*
- * Free a string list
+ * Free a string list. Sets the pointed to pointer to NULL.
  */
-void strlist_free(struct strlist *list)
+void strlist_free(struct strlist **listp)
 {
-	if (list) {
-		struct strlist_entry *e, *tmp;
+	struct strlist *list = *listp;
+	struct strlist_entry *e, *tmp;
 
-                if (list->uniq)
-                    hash_free(&list->hash);
+	if (!list)
+		return;
 
-		list_for_each_safe(e, tmp, list->head)
-			nasm_free(e);
+	if (list->uniq)
+		hash_free(&list->hash);
 
-		nasm_free(list);
-	}
+	list_for_each_safe(e, tmp, list->head)
+		nasm_free(e);
+
+	nasm_free(list);
+	*listp = NULL;
 }
 
 /*
@@ -187,3 +190,17 @@ void *strlist_linearize(const struct strlist *list, char sep)
 
 	return buf;
 }
+
+/*
+ * Output a string list to a file. The separator can be any string.
+ */
+void strlist_write(const struct strlist *list, const char *sep, FILE *f)
+{
+	const struct strlist_entry *sl;
+	size_t seplen = strlen(sep);
+
+	strlist_for_each(sl, list) {
+		fwrite(sl->str, 1, sl->size - 1, f);
+		fwrite(sep, 1, seplen, f);
+	}
+}