Bump the trunk major version to 13

and clear the release notes.

GitOrigin-RevId: 5369517d20dd362a178a1b2d6c398d8898ee4620
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 8ae32fb..05131bd 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -24,7 +24,7 @@
   project(libunwind LANGUAGES C CXX ASM)
 
   set(PACKAGE_NAME libunwind)
-  set(PACKAGE_VERSION 12.0.0git)
+  set(PACKAGE_VERSION 13.0.0git)
   set(PACKAGE_STRING "${PACKAGE_NAME} ${PACKAGE_VERSION}")
   set(PACKAGE_BUGREPORT "llvm-bugs@lists.llvm.org")
 
diff --git a/docs/conf.py b/docs/conf.py
index 6217ead..07ffba7 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -48,9 +48,9 @@
 # built documents.
 #
 # The short X.Y version.
-version = '12.0'
+version = '13.0'
 # The full version, including alpha/beta/rc tags.
-release = '12.0'
+release = '13.0'
 
 # The language for content autogenerated by Sphinx. Refer to documentation
 # for a list of supported languages.