fix for msvc toolset version overflow

conan/tools/cmake/toolchain/blocks.py

@@ -697,7 +697,8 @@ def get_toolset(generator, conanfile):
                 compiler_update = str(settings.compiler.update)
                 if compiler_update != "None":  # It is full one(19.28), not generic 19.2X
                     # The equivalent of compiler 19.26 is toolset 14.26
-                    toolset = "version=14.{}{}".format(compiler_version[-1], compiler_update)
+                    compiler_ver = int(compiler_version[-1]) * 10 + int(compiler_update)
+                    toolset = "version=14.{}".format(compiler_ver)
                 else:
                     toolset = msvc_version_to_toolset_version(compiler_version)
         elif compiler == "clang":

conans/test/unittests/tools/cmake/test_cmaketoolchain.py

@@ -198,7 +198,7 @@ def conanfile_msvc():
     c = ConanFile(None)
     c.settings = Settings({"os": ["Windows"],
                            "compiler": {"msvc": {"version": ["193"], "cppstd": ["20"],
-                                                 "update": [None]}},
+                                                 "update": ["ANY"]}},
                            "build_type": ["Release"],
                            "arch": ["x86"]})
     c.settings.build_type = "Release"
@@ -223,6 +223,19 @@ def test_toolset(conanfile_msvc):
     assert 'CMAKE_CXX_STANDARD 20' in toolchain.content
 
 
+def test_toolset_update_version(conanfile_msvc):
+    conanfile_msvc.settings.compiler.update = "8"
+    toolchain = CMakeToolchain(conanfile_msvc)
+    assert 'set(CMAKE_GENERATOR_TOOLSET "version=14.38" CACHE STRING "" FORCE)' in toolchain.content
+
+
+def test_toolset_update_version_overflow(conanfile_msvc):
+    # https://github.com/conan-io/conan/issues/15583
+    conanfile_msvc.settings.compiler.update = "10"
+    toolchain = CMakeToolchain(conanfile_msvc)
+    assert 'set(CMAKE_GENERATOR_TOOLSET "version=14.40" CACHE STRING "" FORCE)' in toolchain.content
+
+
 def test_toolset_x64(conanfile_msvc):
     # https://github.com/conan-io/conan/issues/11144
     conanfile_msvc.conf.define("tools.cmake.cmaketoolchain:toolset_arch", "x64")