wasm2c: Cleanup TLS: check for __thread and declare TLS vars only whe…

…n needed
WebAssembly · Oct 27, 2024 · d90ce1a · d90ce1a
1 parent b8d82ac
commit d90ce1a
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diff --git a/wasm2c/wasm-rt-impl.c b/wasm2c/wasm-rt-impl.c
@@ -73,7 +73,9 @@ WASM_RT_THREAD_LOCAL uint32_t wasm_rt_saved_call_stack_depth;
 static WASM_RT_THREAD_LOCAL void* g_alt_stack = NULL;
 #endif
 
+#ifndef WASM_RT_TRAP_HANDLER
 WASM_RT_THREAD_LOCAL wasm_rt_jmp_buf g_wasm_rt_jmp_buf;
+#endif
 
 #ifdef WASM_RT_TRAP_HANDLER
 extern void WASM_RT_TRAP_HANDLER(wasm_rt_trap_t code);

diff --git a/wasm2c/wasm-rt-impl.h b/wasm2c/wasm-rt-impl.h
@@ -27,8 +27,10 @@
 extern "C" {
 #endif
 
+#ifndef WASM_RT_TRAP_HANDLER
 /** A setjmp buffer used for handling traps. */
 extern WASM_RT_THREAD_LOCAL wasm_rt_jmp_buf g_wasm_rt_jmp_buf;
+#endif
 
 #if WASM_RT_STACK_DEPTH_COUNT
 /** Saved call stack depth that will be restored in case a trap occurs. */

diff --git a/wasm2c/wasm-rt.h b/wasm2c/wasm-rt.h
@@ -81,6 +81,10 @@ extern "C" {
 
 #ifdef _MSC_VER
 #define WASM_RT_THREAD_LOCAL __declspec(thread)
+// We use __thread on POSIXy systems. This is disabled on Apple systems right
+// now due to sporadic test failures.
+#elif (defined(__GNUC__) || defined(__clang__)) && !defined(__APPLE__)
+#define WASM_RT_THREAD_LOCAL __thread
 #elif defined(WASM_RT_C11_AVAILABLE)
 #define WASM_RT_THREAD_LOCAL _Thread_local
 #else