Fix Savannah bug #106: keep separate track of which variable we are

expanding, and use that info when generating error messages instead of
the file info, where appropriate.

1 files changed, 23 insertions, 17 deletions

diff --git a/expand.c b/expand.c
index 82e12f7..d25afef 100644
--- a/expand.c
+++ b/expand.c
@@ -26,6 +26,10 @@ Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.  */
 #include "variable.h"
 #include "rule.h"
 
+/* Initially, any errors reported when expanding strings will be reported
+   against the file where the error appears.  */
+const struct floc **expanding_var = &reading_file;
+
 /* The next two describe the variable output buffer.
    This buffer is used to hold the variable-expansion of a line of the
    makefile.  It is made bigger with realloc whenever it is too small.
@@ -95,14 +99,25 @@ char *
 recursively_expand_for_file (struct variable *v, struct file *file)
 {
   char *value;
-  struct variable_set_list *save = 0;
+  const struct floc *this_var;
+  const struct floc **saved_varp;
+  struct variable_set_list *save;
   int set_reading = 0;
 
+  /* Don't install a new location if this location is empty.
+     This can happen for command-line variables, builtin variables, etc.  */
+  saved_varp = expanding_var;
+  if (v->fileinfo.filenm)
+    {
+      this_var = &v->fileinfo;
+      expanding_var = &this_var;
+    }
+
   if (v->expanding)
     {
       if (!v->exp_count)
         /* Expanding V causes infinite recursion.  Lose.  */
-        fatal (reading_file,
+        fatal (this_var,
                _("Recursive variable `%s' references itself (eventually)"),
                v->name);
       --v->exp_count;
@@ -118,7 +133,7 @@ recursively_expand_for_file (struct variable *v, struct file *file)
   if (!reading_file)
     {
       set_reading = 1;
-      reading_file = &v->fileinfo;
+      reading_file = this_var;
     }
 
   v->expanding = 1;
@@ -130,9 +145,12 @@ recursively_expand_for_file (struct variable *v, struct file *file)
 
   if (set_reading)
     reading_file = 0;
+
   if (file)
     current_variable_set_list = save;
 
+  expanding_var = saved_varp;
+
   return value;
 }
 
@@ -245,7 +263,7 @@ variable_expand_string (char *line, char *string, long length)
 	    end = strchr (beg, closeparen);
 	    if (end == 0)
               /* Unterminated variable reference.  */
-              fatal (reading_file, _("unterminated variable reference"));
+              fatal (*expanding_var, _("unterminated variable reference"));
 	    p1 = lindex (beg, end, '$');
 	    if (p1 != 0)
 	      {
@@ -371,19 +389,7 @@ variable_expand_string (char *line, char *string, long length)
 
 	  /* A $ followed by a random char is a variable reference:
 	     $a is equivalent to $(a).  */
-	  {
-	    /* We could do the expanding here, but this way
-	       avoids code repetition at a small performance cost.  */
-	    char name[5];
-	    name[0] = '$';
-	    name[1] = '(';
-	    name[2] = *p;
-	    name[3] = ')';
-	    name[4] = '\0';
-	    p1 = allocated_variable_expand (name);
-	    o = variable_buffer_output (o, p1, strlen (p1));
-	    free (p1);
-	  }
+          o = reference_variable (o, p, 1);
 
 	  break;
 	}