Update version to 4.0.0RC3.

Bumps the pre-commit-hooks group with 1 update: [https://github.com/rhysd/actionlint](https://github.com/rhysd/actionlint).


Updates `https://github.com/rhysd/actionlint` from v1.7.11 to 1.7.12
- [Release notes](https://github.com/rhysd/actionlint/releases)
- [Changelog](https://github.com/rhysd/actionlint/blob/main/CHANGELOG.md)
- [Commits](https://github.com/rhysd/actionlint/compare/v1.7.11...v1.7.12)

---
updated-dependencies:
- dependency-name: https://github.com/rhysd/actionlint
  dependency-version: 1.7.12
  dependency-type: direct:production
  dependency-group: pre-commit-hooks
...

Signed-off-by: dependabot[bot] <support@github.com>

.github/dependabot.yml

@@ -29,3 +29,5 @@ updates:
       pre-commit-hooks:
         patterns:
           - "*"
+    cooldown:
+      default-days: 7

.pre-commit-config.yaml

@@ -85,7 +85,7 @@ repos:
         args: [--whitespaces-count, "2"]
         exclude: Makefile$
   - repo: https://github.com/rhysd/actionlint
-    rev: v1.7.11
+    rev: v1.7.12
     hooks:
       - id: actionlint
         name: run actionlint

README.md

@@ -51,6 +51,8 @@ To get mruby, you can download the stable version 4.0.0 from the official mruby
 GitHub repository or clone the trunk of the mruby source tree with the "git
 clone" command. You can also install and compile mruby using [ruby-install](https://github.com/postmodern/ruby-install), [ruby-build](https://github.com/rbenv/ruby-build), [rvm](https://github.com/rvm/rvm), [conda](https://anaconda.org/channels/conda-forge/packages/mruby/overview) or [Homebrew](https://formulae.brew.sh/formula/mruby).
 
+The release candidate version 4.0.0 of mruby can be downloaded via the following URL: [https://github.com/mruby/mruby/archive/4.0.0-rc3.zip](https://github.com/mruby/mruby/archive/4.0.0-rc3.zip)
+
 The latest development version of mruby can be downloaded via the following URL: [https://github.com/mruby/mruby/zipball/master](https://github.com/mruby/mruby/zipball/master)
 
 The trunk of the mruby source tree can be checked out with the

include/mruby/version.h

@@ -57,7 +57,7 @@ MRB_BEGIN_DECL
 /*
  * Patch level string. (optional)
  */
-#define MRUBY_PATCHLEVEL_STR ""
+#define MRUBY_PATCHLEVEL_STR "RC3"
 
 #ifndef MRUBY_PATCHLEVEL_STR
 # if MRUBY_PATCHLEVEL < 0
@@ -80,7 +80,7 @@ MRB_BEGIN_DECL
 /*
  * Release year.
  */
-#define MRUBY_RELEASE_YEAR 2025
+#define MRUBY_RELEASE_YEAR 2026
 
 /*
  * Release month.
@@ -90,7 +90,7 @@ MRB_BEGIN_DECL
 /*
  * Release day.
  */
-#define MRUBY_RELEASE_DAY 20
+#define MRUBY_RELEASE_DAY 2
 
 /*
  * Release date as a string.

mrbgems/mruby-socket/mrblib/socket.rb

@@ -701,13 +701,11 @@ class UDPSocket < IPSocket
   #   data, addr = sock.recvfrom_nonblock(1024)
   #
   def recvfrom_nonblock(*args)
-    s = self
     begin
       self._setnonblock(true)
       self.recvfrom(*args)
     ensure
-      # XXX: self is a SystemcallException here! (should be bug)
-      s._setnonblock(false)
+      self._setnonblock(false)
     end
   end
 

src/vm.c

@@ -134,19 +134,29 @@ static inline void
 envadjust(mrb_state *mrb, mrb_value *oldbase, mrb_value *newbase)
 {
   mrb_callinfo *ci = mrb->c->cibase;
-  ptrdiff_t delta = newbase - oldbase;
+  /*
+   * Byte-level calculation to avoid truncation when allocator alignment is
+   * smaller than sizeof(mrb_value).
+   * eg: MRB_NO_BOXING + MRB_INT64 with MRB_32BIT => sizeof(mrb_value)=16
+   *     And when memory allocator's alignment is 8 bytes
+   * Pointer subtraction on mrb_value* would truncate (8/16 -> 0).
+   * So, we use char* for pointer calculation to get the correct offset in bytes,
+   * then apply that offset to mrb_value* pointers.
+   */
+  ptrdiff_t off = (char *)newbase - (char *)oldbase;
 
-  if (delta == 0) return;
+  if (off == 0) return;
   while (ci <= mrb->c->ci) {
     struct REnv *e = mrb_vm_ci_env(ci);
 
+    mrb_value *new_stack = (mrb_value *)((char *)ci->stack + off);
+
     if (e) {
       mrb_assert(e->cxt == mrb->c && MRB_ENV_ONSTACK_P(e));
       mrb_assert(e->stack == ci->stack);
-
-      e->stack += delta;
+      e->stack = new_stack;
     }
-    ci->stack += delta;
+    ci->stack = new_stack;
     ci++;
   }
 }