From cb21e44e941ece5fc751ba61b941270229b079c0 Mon Sep 17 00:00:00 2001
From: FellippeHeitor <fellippeheitor@gmail.com>
Date: Sun, 31 Mar 2019 20:22:53 -0300
Subject: [PATCH] If merely redefining a CONST with same value, just issue a
 warning.

---
 source/qb64.bas | 43 +++++++++++++++++++++++++++++++++++++++----
 1 file changed, 39 insertions(+), 4 deletions(-)

diff --git a/source/qb64.bas b/source/qb64.bas
index c46afe1af..6ebcccff4 100644
--- a/source/qb64.bas
+++ b/source/qb64.bas
@@ -112,7 +112,7 @@ DIM SHARED ConsoleMode, No_C_Compile_Mode, Cloud, NoIDEMode
 DIM SHARED VerboseMode AS _BYTE, CMDLineFile AS STRING
 
 DIM SHARED totalUnusedVariables AS LONG, usedVariableList$, bypassNextVariable AS _BYTE
-DIM SHARED totalWarnings AS LONG, warningListItems AS LONG
+DIM SHARED totalWarnings AS LONG, warningListItems AS LONG, lastWarningHeader AS STRING
 DIM SHARED ExeIconSet AS LONG
 DIM SHARED VersionInfoSet AS _BYTE
 
@@ -1435,6 +1435,7 @@ usedVariableList$ = ""
 totalUnusedVariables = 0
 totalWarnings = 0
 warningListItems = 0
+lastWarningHeader = ""
 REDIM SHARED warning$(1000)
 uniquenumbern = 0
 
@@ -2353,7 +2354,31 @@ DO
                             hashres = HashFind(hashname$, hashchkflags, hashresflags, hashresref)
                             DO WHILE hashres
                                 IF hashresflags AND HASHFLAG_CONSTANT THEN
-                                    IF constsubfunc(hashresref) = subfuncn THEN a$ = "Name already in use": GOTO errmes
+                                    IF constsubfunc(hashresref) = subfuncn THEN
+                                        'If merely redefining a CONST with same value
+                                        'just issue a warning instead of an error
+                                        issueWarning = 0
+                                        IF t AND ISSTRING THEN
+                                            IF conststring(hashresref) = e$ THEN issueWarning = -1
+                                        ELSE
+                                            IF t AND ISFLOAT THEN
+                                                IF constfloat(hashresref) = constval## THEN issueWarning = -1
+                                            ELSE
+                                                IF t AND ISUNSIGNED THEN
+                                                    IF constuinteger(hashresref) = constval~&& THEN issueWarning = -1
+                                                ELSE
+                                                    IF constinteger(hashresref) = constval&& THEN issueWarning = -1
+                                                END IF
+                                            END IF
+                                        END IF
+                                        IF issueWarning THEN
+                                            addWarning 0, "Constant already defined (same value):"
+                                            addWarning linenumber, n$
+                                            GOTO constAddDone
+                                        ELSE
+                                            a$ = "Name already in use": GOTO errmes
+                                        END IF
+                                    END IF
                                 END IF
                                 IF hashresflags AND HASHFLAG_RESERVED THEN
                                     a$ = "Name already in use": GOTO errmes
@@ -2391,6 +2416,8 @@ DO
                                 END IF
                             END IF
 
+                            constAddDone:
+
                             IF pending THEN
                                 'l$ = l$ + sp2 + ","
                                 GOTO constdefpendingpp
@@ -24994,11 +25021,19 @@ SUB manageVariableList (name$, __cname$, action AS _BYTE)
 END SUB
 
 SUB addWarning (lineNumber AS LONG, text$)
+    IF lineNumber > 0 THEN
+        totalWarnings = totalWarnings + 1
+    ELSE
+        IF lastWarningHeader = text$ THEN
+            EXIT SUB
+        ELSE
+            lastWarningHeader = text$
+        END IF
+    END IF
+
     warningListItems = warningListItems + 1
     IF warningListItems > UBOUND(warning$) THEN REDIM _PRESERVE warning$(warningListItems + 999)
-
     warning$(warningListItems) = MKL$(lineNumber) + text$
-    IF lineNumber > 0 THEN totalWarnings = totalWarnings + 1
 END SUB
 
 '$INCLUDE:'utilities\strings.bas'