diff --git a/source/compiler/sc1.c b/source/compiler/sc1.c
index a50409e..308da67 100644
--- a/source/compiler/sc1.c
+++ b/source/compiler/sc1.c
@@ -1982,25 +1982,30 @@ void sc_attachdocumentation(symbol *sym)
   /* first check the size */
   length=0;
   for (line=0; (str=get_docstring(line))!=NULL && *str!=sDOCSEP; line++) {
-    if (length>0)
-      length++;   /* count 1 extra for a separating space */
-    length+=strlen(str);
+    if (str[0]!='\0') {
+      if (length>0)
+        length++;   /* count 1 extra for a separating space */
+      length+=strlen(str);
+    }
   } /* for */
-  if (sym==NULL && sc_documentation!=NULL) {
-    length += strlen(sc_documentation) + 1 + 4; /* plus 4 for "<p/>" */
-    assert(length>strlen(sc_documentation));
-  } /* if */
-
   if (length>0) {
-    /* allocate memory for the documentation */
-    if (sym!=NULL && sym->documentation!=NULL)
+    if (sym==NULL && sc_documentation!=NULL) {
+      length += strlen(sc_documentation) + 1 + 4; /* plus 4 for "<p/>" */
+      assert(length > strlen(sc_documentation));
+    } else if (sym!=NULL && sym->documentation!=NULL) {
       length+=strlen(sym->documentation) + 1 + 4;/* plus 4 for "<p/>" */
+      assert(length > strlen(sym->documentation));
+    } /* if */
+
+    /* allocate memory for the documentation */
     doc=(char*)malloc((length+1)*sizeof(char));
     if (doc!=NULL) {
       /* initialize string or concatenate */
       if (sym==NULL && sc_documentation!=NULL) {
         strcpy(doc,sc_documentation);
         strcat(doc,"<p/>");
+        free(sc_documentation);
+        sc_documentation=NULL;
       } else if (sym!=NULL && sym->documentation!=NULL) {
         strcpy(doc,sym->documentation);
         strcat(doc,"<p/>");
@@ -2011,9 +2016,11 @@ void sc_attachdocumentation(symbol *sym)
       } /* if */
       /* collect all documentation */
       while ((str=get_docstring(0))!=NULL && *str!=sDOCSEP) {
-        if (doc[0]!='\0')
-          strcat(doc," ");
-        strcat(doc,str);
+        if (str[0]!='\0') {
+          if (doc[0]!='\0')
+            strcat(doc," ");
+          strcat(doc,str);
+        }
         delete_docstring(0);
       } /* while */
       if (str!=NULL) {
@@ -2021,12 +2028,12 @@ void sc_attachdocumentation(symbol *sym)
         assert(*str==sDOCSEP);
         delete_docstring(0);
       } /* if */
-      if (sym!=NULL) {
+      if (sym==NULL) {
+        assert(sc_documentation==NULL);
+        sc_documentation=doc;
+      } else {
         assert(sym->documentation==NULL);
         sym->documentation=doc;
-      } else {
-        free(sc_documentation);
-        sc_documentation=doc;
       } /* if */
     } /* if */
   } else {