From 48d58ba09599ae020419feb15dee80d8958edf83 Mon Sep 17 00:00:00 2001
From: Rangi <sylvie.oukaour+rangi42@gmail.com>
Date: Fri, 6 Mar 2026 22:01:37 -0500
Subject: [PATCH] Pass `-Wdangling-alias` to Bison 3.5 or newer

`bison -Wall` enables all diagnostics except `-Wcounterexamples`
(added in 3.7; we already pass it), `-Wyacc` (which we do not need),
and `-Wdangling-alias` (added in 3.5).
---
 src/CMakeLists.txt | 7 +++++--
 src/bison.sh       | 4 ++--
 2 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 70ebfe63..26d9dd4d 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -14,15 +14,18 @@ set(common_src
 
 find_package(BISON 3.0.0 REQUIRED)
 set(BISON_FLAGS "-Wall -Dlr.type=ielr")
-# Set some optimization flags on versions that support them
+# Set some flags on versions that support them
 if(BISON_VERSION VERSION_GREATER_EQUAL "3.5")
-  set(BISON_FLAGS "${BISON_FLAGS} -Dparse.lac=full -Dapi.token.raw=true")
+  set(BISON_FLAGS "${BISON_FLAGS} -Dparse.lac=full -Dapi.token.raw=true -Wdangling-alias")
 endif()
 if(BISON_VERSION VERSION_GREATER_EQUAL "3.6")
   set(BISON_FLAGS "${BISON_FLAGS} -Dparse.error=detailed")
 else()
   set(BISON_FLAGS "${BISON_FLAGS} -Dparse.error=verbose")
 endif()
+if(BISON_VERSION VERSION_GREATER_EQUAL "3.7")
+  set(BISON_FLAGS "${BISON_FLAGS} -Wcounterexamples")
+endif()
 
 BISON_TARGET(ASM_PARSER "asm/parser.y"
              "${PROJECT_SOURCE_DIR}/src/asm/parser.cpp"
diff --git a/src/bison.sh b/src/bison.sh
index 0e58c0cd..732b124e 100755
--- a/src/bison.sh
+++ b/src/bison.sh
@@ -14,9 +14,9 @@ fi
 
 BISON_FLAGS="-Wall -Dlr.type=ielr"
 
-# Set some optimization flags on versions that support them
+# Set some flags on versions that support them
 if [ "$BISON_MAJOR" -ge 4 ] || [ "$BISON_MAJOR" -eq 3 ] && [ "$BISON_MINOR" -ge 5 ]; then
-	BISON_FLAGS="$BISON_FLAGS -Dparse.lac=full -Dapi.token.raw=true"
+	BISON_FLAGS="$BISON_FLAGS -Dparse.lac=full -Dapi.token.raw=true -Wdangling-alias"
 fi
 if [ "$BISON_MAJOR" -ge 4 ] || [ "$BISON_MAJOR" -eq 3 ] && [ "$BISON_MINOR" -ge 6 ]; then
 	BISON_FLAGS="$BISON_FLAGS -Dparse.error=detailed"