test: Add a testcase for atomic helpers

test/Makefile

@@ -92,6 +92,7 @@ ifneq ($(HAVE_CFGUARD),)
     TESTS_CFGUARD = cfguard-test
     TESTS_ASAN_CFGUARD = $(TESTS_ASAN)
 endif
+TESTS_ATOMIC = atomic-helpers
 
 TARGETS_C = $(addsuffix $(EXEEXT), $(TESTS_C))
 TARGETS_C_DLL = $(addsuffix $(DLLEXT), $(TESTS_C_DLL))
@@ -120,6 +121,7 @@ TARGETS_ASAN = $(addsuffix -asan$(EXEEXT), $(TESTS_ASAN))
 TARGETS_UBSAN = $(addsuffix $(EXEEXT), $(TESTS_UBSAN))
 TARGETS_ASAN_CFGUARD = $(addsuffix -asan-cfguard$(EXEEXT), $(TESTS_ASAN_CFGUARD))
 TARGETS_OMP = $(addsuffix $(EXEEXT), $(TESTS_OMP))
+TARGETS_ATOMIC = $(addsuffix $(EXEEXT), $(TESTS_ATOMIC))
 
 TARGETS = \
     $(TARGETS_C) $(TARGETS_C_DLL) $(TARGETS_C_LINK_DLL) $(TARGETS_C_NO_BUILTIN) $(TARGETS_C_ANSI_STDIO) \
@@ -128,7 +130,7 @@ TARGETS = \
     $(TARGETS_IDL) $(TARGETS_RES) \
     $(TARGETS_OTHER_TARGETS) $(TARGETS_UWP) $(TARGETS_UWP_FAIL) \
     $(TARGETS_ASAN) $(TARGETS_UBSAN) $(TARGETS_ASAN_CFGUARD) \
-    $(TARGETS_OMP)
+    $(TARGETS_OMP) $(TARGETS_ATOMIC)
 
 # crt-test-fortify doesn't trigger failures
 FAILURE_TESTS = \
@@ -197,6 +199,9 @@ $(TARGETS_ASAN_CFGUARD): %-asan-cfguard$(EXEEXT): %.c
 $(TARGETS_OMP): %$(EXEEXT): %.c
 	$(CC) $(CPPFLAGS) $(CFLAGS) $< -o $@ -fopenmp=libomp
 
+$(TARGETS_ATOMIC): %$(EXEEXT): %.c
+	$(CC) $(CPPFLAGS) $(CFLAGS) $< -o $@ -Wno-atomic-alignment
+
 %.h: %.idl
 	$(WIDL) $< -h -o $@
 

test/atomic-helpers.c

@@ -0,0 +1,41 @@
+/*
+ * Copyright (c) 2023 Martin Storsjo
+ *
+ * This file is part of llvm-mingw.
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <stdatomic.h>
+
+struct large {
+    int data[20];
+};
+
+typedef struct large type;
+
+_Atomic type value;
+
+type get(void) {
+    return atomic_load(&value);
+}
+
+type myValue;
+
+int lockfree;
+
+int main(int argc, char* argv[]) {
+    myValue = get();
+    lockfree = atomic_is_lock_free(&value);
+    return 0;
+}