From b1d4d8d6685ad14a3d2dbb9e958d618b549c3247 Mon Sep 17 00:00:00 2001
From: Stephen Heumann <stephenheumann@gmail.com>
Date: Fri, 29 Jan 2021 12:49:28 -0600
Subject: [PATCH] Give errors for certain invalid compound assignment
 expressions.

The following example shows cases that were erroneously permitted before:

int main(void) {
        int i, *p;
        i *= p;
        i <<= 5.0;
        i <<= (void)1;
}
---
 Expression.pas | 6 ++++--
 cc.notes       | 2 ++
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/Expression.pas b/Expression.pas
index 07752a8..e0814e4 100644
--- a/Expression.pas
+++ b/Expression.pas
@@ -3011,11 +3011,13 @@ case tree^.token.kind of
          kind := lType^.kind;
       GenerateCode(tree^.right);
       if expressionType^.kind <> scalarType then
-         if tree^.token.kind in [pluseqop,minuseqop] then
-            Error(66);
+         Error(66);
       if tree^.token.kind in [gtgteqop,ltlteqop] then
          if kind = scalarType then
             if expressionType^.kind = scalarType then begin
+               if expressionType^.baseType in 
+                  [cgReal,cgDouble,cgComp,cgExtended,cgVoid] then
+                  Error(66);
                et := UsualUnaryConversions;
                if et <> Unary(ltype^.baseType) then begin
                   Gen2(pc_cnv, et, ord(Unary(ltype^.baseType)));
diff --git a/cc.notes b/cc.notes
index 6a4a913..2b74ba9 100644
--- a/cc.notes
+++ b/cc.notes
@@ -998,6 +998,8 @@ int foo(int[42]);
 
 128. The ++ and -- operators often would not work correctly on bit-fields, or on floating-point values that were in a structure or were accessed via a pointer.
 
+129. Certain invalid compound assignment expressions were erroneously permitted.
+
 -- Bugs from C 2.1.0 that have been fixed -----------------------------------
 
 1.  In some situations, fread() reread the first 1K or so of the file.