From 662ce928a7fb31117bc584aad10d9c5c82689abd Mon Sep 17 00:00:00 2001
From: Koichi Sasada <ko1@atdot.net>
Date: Fri, 19 Apr 2024 13:21:55 +0900
Subject: [PATCH] `RUBY_TRY_UNUSED_BLOCK_WARNING_STRICT`

`RUBY_TRY_UNUSED_BLOCK_WARNING_STRICT=1 ruby ...` will enable
strict check for unused block warning.

This option is only for trial to compare the results so the
envname is not considered well.
Should be removed before Ruby 3.4.0 release.
---
 compile.c       |  7 +++++--
 vm.c            |  6 ++++++
 vm_core.h       |  1 +
 vm_insnhelper.c | 10 +++++++---
 4 files changed, 19 insertions(+), 5 deletions(-)

diff --git a/compile.c b/compile.c
index 853fadf5b0..725c65b451 100644
--- a/compile.c
+++ b/compile.c
@@ -2006,8 +2006,11 @@ iseq_set_use_block(rb_iseq_t *iseq)
         body->param.flags.use_block = 1;
 
         rb_vm_t *vm = GET_VM();
-        st_data_t key = (st_data_t)rb_intern_str(body->location.label); // String -> ID
-        st_insert(vm->unused_block_warning_table, key, 1);
+
+        if (!vm->unused_block_warning_strict) {
+            st_data_t key = (st_data_t)rb_intern_str(body->location.label); // String -> ID
+            st_insert(vm->unused_block_warning_table, key, 1);
+        }
     }
 }
 
diff --git a/vm.c b/vm.c
index b4f6a4bf16..0b3edea58c 100644
--- a/vm.c
+++ b/vm.c
@@ -4261,6 +4261,12 @@ Init_BareVM(void)
     vm->constant_cache = rb_id_table_create(0);
     vm->unused_block_warning_table = st_init_numtable();
 
+    // TODO: remove before Ruby 3.4.0 release
+    const char *s = getenv("RUBY_TRY_UNUSED_BLOCK_WARNING_STRICT");
+    if (s && strcmp(s, "1") == 0) {
+        vm->unused_block_warning_strict = true;
+    }
+
     // setup main thread
     th->nt = ZALLOC(struct rb_native_thread);
     th->vm = vm;
diff --git a/vm_core.h b/vm_core.h
index 2400b02c7e..a8a3dde58a 100644
--- a/vm_core.h
+++ b/vm_core.h
@@ -774,6 +774,7 @@ typedef struct rb_vm_struct {
     struct rb_id_table *negative_cme_table;
     st_table *overloaded_cme_table; // cme -> overloaded_cme
     st_table *unused_block_warning_table;
+    bool unused_block_warning_strict;
 
     // This id table contains a mapping from ID to ICs. It does this with ID
     // keys and nested st_tables as values. The nested tables have ICs as keys
diff --git a/vm_insnhelper.c b/vm_insnhelper.c
index 249bb49ea7..377f7b513a 100644
--- a/vm_insnhelper.c
+++ b/vm_insnhelper.c
@@ -2978,6 +2978,7 @@ warn_unused_block(const rb_callable_method_entry_t *cme, const rb_iseq_t *iseq,
 {
     rb_vm_t *vm = GET_VM();
     st_table *dup_check_table = vm->unused_block_warning_table;
+    st_data_t key;
 
     union {
         VALUE v;
@@ -2989,14 +2990,17 @@ warn_unused_block(const rb_callable_method_entry_t *cme, const rb_iseq_t *iseq,
     };
 
     // relax check
-    st_data_t key = (st_data_t)cme->def->original_id;
+    if (!vm->unused_block_warning_strict) {
+        key = (st_data_t)cme->def->original_id;
 
-    if (st_lookup(dup_check_table, key, NULL)) {
-        return;
+        if (st_lookup(dup_check_table, key, NULL)) {
+            return;
+        }
     }
 
     // strict check
     // make unique key from pc and me->def pointer
+    key = 0;
     for (int i=0; i<SIZEOF_VALUE; i++) {
         // fprintf(stderr, "k1:%3d k2:%3d\n", k1.b[i], k2.b[SIZEOF_VALUE-1-i]);
         key |= (st_data_t)(k1.b[i] ^ k2.b[SIZEOF_VALUE-1-i]) << (8 * i);