From e70340301754484f677559d88a442a7493034c1f Mon Sep 17 00:00:00 2001
From: Olaf Seibert <rhialto@falu.nl>
Date: Tue, 12 May 2015 22:59:21 +0200
Subject: [PATCH] Bring .ENDM label in correspondence with the manual.

---
 macros.c | 55 ++++++++-----------------------------------------------
 1 file changed, 8 insertions(+), 47 deletions(-)

diff --git a/macros.c b/macros.c
index 82de022..11ffa18 100644
--- a/macros.c
+++ b/macros.c
@@ -74,7 +74,6 @@ void read_body(
     int called)
 {
     int             nest;
-    unsigned int    self_redef = 0;
 
     /* Read the stream in until the end marker is hit */
 
@@ -107,67 +106,29 @@ void read_body(
         if (op->section->type == SECTION_PSEUDO) {
             if (op->value == P_MACRO || op->value == P_REPT || op->value == P_IRP || op->value == P_IRPC) {
                 nest++;
-                self_redef <<= 1;
-                if (op->value == P_MACRO) {
-                    /* Check for self-redefinition. If that occurs,
-                     * we can't currently cut the outermost macro definition
-                     * short when we encounter .ENDM <self>.
-                     * self_redef keeps a "stack" of booleans for the
-                     * currently nested levels, indicating whether each
-                     * level is a self-redefinition.
-                     */
-                    char *nested_name = get_symbol(cp, &cp, NULL);
-                    if (nested_name != NULL) {
-                        if (strcmp(nested_name, name) == 0) {
-                            self_redef |= 1;
-                        }
-                        free(nested_name);
-                    }
-                }
             }
 
             if (op->value == P_ENDM || op->value == P_ENDR) {
                 nest--;
-                /* If there's a name on the .ENDM, then */
-                /* close the body early if it matches the definition */
-                /* That is however a bad idea for this case:
-                 * .MACRO FAB$BT DEF
-                 * .MCALL DEF
-                 *         DEF    FB$BID,3
-                 * ...
-                 * .MACRO FAB$BT DEF
-                 * .ENDM FAB$BT
-                 * .ENDM FAB$BT
-                 * Therefore we are a bit more selective.
-                 *
-                 * (in fact, on page 7-3 of the manual, there is no
-                 * allowance for early termination of macros, but instead
-                 * the name is checked and if it doesn't match the currently
-                 * defined macro, an error code A is issued.
+                /* If there's a name on the .ENDM, then
+                 * check if the name matches the one on .MACRO.
+                 * See page 7-3.
+                 * Since we don't keep a stack of nested
+                 * .MACRO names, just check for the outer one.
                  */
-                if (!self_redef && nest > 0 &&
-                        name && op->value == P_ENDM) {
+                if (nest == 0 && name && op->value == P_ENDM) {
                     cp = skipwhite(cp);
                     if (!EOL(*cp)) {
                         char           *label = get_symbol(cp, &cp, NULL);
 
                         if (label) {
-                            if (strcmp(label, name) == 0) {
-                                /* Something similar to the following code
-                                 * maybe later, if we do need accurate named
-                                 * escapes from nested macro definitions:
-                                while (!(self_redef & 1)) {
-                                    nest--;
-                                    self_redef >>= 1;
-                                }
-                                 */
-                                nest = 0;       /* End of macro body. */
+                            if (strcmp(label, name) != 0) {
+                                report(stack->top, ".ENDM '%s' does not match .MACRO '%s'\n", label, name);
                             }
                             free(label);
                         }
                     }
                 }
-                self_redef >>= 1;
             }
 
             if (nest == 0)