From 54ddefe4103d9adc7b64adf2ab2dab3fe13a400d Mon Sep 17 00:00:00 2001
From: Olly Betts <olly@survex.com>
Date: Wed, 27 Jul 2022 13:45:08 +1200
Subject: [PATCH] Revert "Modify fix for << in array size"

This reverts commit 0ff9a0959ab0fc537c7db53fb94efb7534b45925.

The modified fix breaks Java and C#, where C constant expressions
get used in the generated target language code in some cases.

Revert this fix for now.
---
 Lib/swiglabels.swg     | 5 -----
 Source/CParse/parser.y | 6 +-----
 Source/Swig/typesys.c  | 4 +++-
 3 files changed, 4 insertions(+), 11 deletions(-)

diff --git a/Lib/swiglabels.swg b/Lib/swiglabels.swg
index 43b2f6edc..b3855665e 100644
--- a/Lib/swiglabels.swg
+++ b/Lib/swiglabels.swg
@@ -121,8 +121,3 @@
 #ifdef __INTEL_COMPILER
 # pragma warning disable 592
 #endif
-
-/* We replace `<<` with `SWIG_LSHIFT` in constant expressions to avoid
- * confusing SWIG's type system into thinking there's a template.
- */
-#define SWIG_LSHIFT <<
diff --git a/Source/CParse/parser.y b/Source/CParse/parser.y
index ce0602f3b..816264de6 100644
--- a/Source/CParse/parser.y
+++ b/Source/CParse/parser.y
@@ -6803,11 +6803,7 @@ exprcompound   : expr PLUS expr {
 		 $$.type = promote($1.type,$3.type);
 	       }
                | expr LSHIFT expr {
-		 /* To avoid confusing SWIG's type system, we replace `<<` with
-		  * `SWIG_LSHIFT` here, then define the latter as a macro in
-		  * the generated wrapper file.
-		  */
-		 $$.val = NewStringf("%s SWIG_LSHIFT %s",COMPOUND_EXPR_VAL($1),COMPOUND_EXPR_VAL($3));
+		 $$.val = NewStringf("%s << %s",COMPOUND_EXPR_VAL($1),COMPOUND_EXPR_VAL($3));
 		 $$.type = promote_type($1.type);
 	       }
                | expr RSHIFT expr {
diff --git a/Source/Swig/typesys.c b/Source/Swig/typesys.c
index 710688a0f..464b89f28 100644
--- a/Source/Swig/typesys.c
+++ b/Source/Swig/typesys.c
@@ -1702,7 +1702,9 @@ void SwigType_remember_clientdata(const SwigType *t, const_String_or_char_ptr cl
 
   if (t) {
     char *ct = Char(t);
-    if (strchr(ct, '<') && !(strstr(ct, "<("))) {
+    const char *lt = strchr(ct, '<');
+    /* Allow for `<<` operator in constant expression for array size. */
+    if (lt && lt[1] != '(' && lt[1] != '<') {
       Printf(stdout, "Bad template type passed to SwigType_remember: %s\n", t);
       assert(0);
     }