[libc] Change LIBC_THREAD_LOCAL to be dependent on LIBC_THREAD_MODE #151527
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@llvm/pr-subscribers-libc Author: William Huynh (saturn691) ChangesThis allows baremetal builds to avoid using thread_local. However, libcxx may be affected by this. Full diff: https://github.com/llvm/llvm-project/pull/151527.diff 1 Files Affected:
diff --git a/libc/src/__support/macros/attributes.h b/libc/src/__support/macros/attributes.h
index c6474673de85a..23f973827b6f9 100644
--- a/libc/src/__support/macros/attributes.h
+++ b/libc/src/__support/macros/attributes.h
@@ -28,7 +28,7 @@
#define LIBC_INLINE_ASM __asm__ __volatile__
#define LIBC_UNUSED __attribute__((unused))
-#ifdef LIBC_TARGET_ARCH_IS_GPU
+#if LIBC_THREAD_MODE == LIBC_THREAD_MODE_SINGLE
#define LIBC_THREAD_LOCAL
#else
#define LIBC_THREAD_LOCAL thread_local
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It seems the CI failure here stems from a manual interrupt- requesting review. |
lntue
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…lvm#151527) When single-threaded mode is selected, all instances of the keyword `LIBC_THREAD_LOCAL` are stubbed out, similar to how it currently works on the GPU. This allows baremetal builds to avoid using thread_local. However, libcxx uses shared headers, so we need to be careful there. Thankfully, there is already an option to disable multithreading in libcxx, so a flag is added such that single-threaded mode is propagated down to libc.
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When single-threaded mode is selected, all instances of the keyword
LIBC_THREAD_LOCALare stubbed out, similar to how it currently works on the GPU. This allows baremetal builds to avoid using thread_local.However, libcxx uses shared headers, so we need to be careful there. Thankfully, there is already an option to disable multithreading in libcxx, so a flag is added such that single-threaded mode is propagated down to libc.