Sync minimum compiler and CMake versions for macOS

CMakeLists.txt

@@ -108,7 +108,7 @@ endif()
 
 # The minimum compiler versions should match those listed in both
 # doc/developers.rst and tools/workspace/cc/repository.bzl.
-set(MINIMUM_APPLE_CLANG_VERSION 11)
+set(MINIMUM_APPLE_CLANG_VERSION 12)
 set(MINIMUM_CLANG_VERSION 9)
 set(MINIMUM_GNU_VERSION 7.5)
 

doc/developers.rst

@@ -85,8 +85,8 @@ Drake requires a compiler running in C++17 mode.
 | Ubuntu 20.04 LTS (Focal Fossa)   |       | 3.16  | | GCC 9.3 (default) |                   | 3.8    |
 |                                  |       |       | | Clang 9           |                   |        |
 +----------------------------------+       +-------+---------------------+-------------------+        |
-| macOS Catalina (10.15)           |       | 3.18  | | Apple LLVM 12.0.0 | | AdoptOpenJDK 15 |        |
-|                                  |       |       | | (Xcode 12.2)      | | (HotSpot JVM)   |        |
+| macOS Catalina (10.15)           |       | 3.19  | | Apple LLVM 12.0.0 | | AdoptOpenJDK 15 |        |
+|                                  |       |       | | (Xcode 12.4)      | | (HotSpot JVM)   |        |
 +----------------------------------+-------+-------+---------------------+-------------------+--------+
 
 CPython is the only Python implementation supported. On Ubuntu, amd64

tools/workspace/cc/repository.bzl

@@ -120,8 +120,8 @@ def _impl(repository_ctx):
     # even if they happen to support the necessary compiler flags.
 
     if compiler_id == "AppleClang":
-        if compiler_version_major < 11:
-            fail("AppleClang compiler version {}.{} is less than 11.0.".format(
+        if compiler_version_major < 12:
+            fail("AppleClang compiler version {}.{} is less than 12.0.".format(
                 compiler_version_major,
                 compiler_version_minor,
             ))