[compiler-rt] Fix __isOSVersionAtLeast for Android (PR #80496)

[Jooyung Han via llvm-commits]

https://github.com/jooyunghan created https://github.com/llvm/llvm-project/pull/80496

Allow pre-release APIs on pre-release devices.

The current implementation requires __ANDROID_API_FUTURE__ to use new APIs on pre-release system. This makes it hard to maintain the codebase because it should be switched a concrete version (e.g. __ANDROID_API_X__ on release of X).

Instead, we can just allow pre-release APIs on pre-release system without mandating the major version of __ANDROID_API_FUTURE__.

Note that this doesn't make API guards just no-op in pre-release builds. We can still rely on its compile-time checks and it still works as expected with release builds. Even with pre-release builds, it's the same as before because we would pass __ANDROID_API_FUTURE__ to make the calls anyway.

>From 50eeec5bae196717e1540221685b95dd50e563e8 Mon Sep 17 00:00:00 2001
From: Jooyung Han <jooyung.han at gmail.com>
Date: Fri, 2 Feb 2024 13:30:06 -0800
Subject: [PATCH] Fix __isOSVersionAtLeast for Android

Allow pre-release APIs on pre-release devices.

The current implementation requires __ANDROID_API_FUTURE__ to use new APIs on pre-release system. This makes it hard to maintain the codebase because it should be switched a concrete version (e.g. __ANDROID_API_X__ on release of X).

Instead, we can just allow pre-release APIs on pre-release system without mandating the major version of __ANDROID_API_FUTURE__.

Note that this doesn't make API guards just no-op in pre-release builds. We can still rely on its compile-time checks and it still works as expected with release builds. Even with pre-release builds, it's the same as before because we would pass __ANDROID_API_FUTURE__ to make the calls anyway.
---
 compiler-rt/lib/builtins/os_version_check.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/compiler-rt/lib/builtins/os_version_check.c b/compiler-rt/lib/builtins/os_version_check.c
index 182eabe7a6ae2..01fae834ab219 100644
--- a/compiler-rt/lib/builtins/os_version_check.c
+++ b/compiler-rt/lib/builtins/os_version_check.c
@@ -316,8 +316,8 @@ int32_t __isOSVersionAtLeast(int32_t Major, int32_t Minor, int32_t Subminor) {
   static pthread_once_t once = PTHREAD_ONCE_INIT;
   pthread_once(&once, readSystemProperties);
 
-  return SdkVersion >= Major ||
-         (IsPreRelease && Major == __ANDROID_API_FUTURE__);
+  // Allow all on pre-release. Note that we still rely on compile-time checks.
+  return SdkVersion >= Major || IsPreRelease;
 }
 
 #else