new file mode 100644
@@ -0,0 +1,15 @@
+/* { dg-do compile { target { tail_call && { c || c++11 } } } } */
+/* { dg-options "-O2" } */
+/* { dg-additional-options "-fdelayed-branch" { target sparc*-*-* } } */
+
+int __attribute__((noinline,noclone,noipa))
+callee (int i)
+{
+ return i * i;
+}
+
+int __attribute__((noinline,noclone,noipa))
+caller (int i)
+{
+ [[gnu::musttail]] return callee (i + 1);
+}
new file mode 100644
@@ -0,0 +1,34 @@
+/* { dg-do compile { target { tail_call && { c || c++11 } } } } */
+
+struct box { char field[256]; int i; };
+
+int __attribute__((noinline,noclone,noipa))
+test_2_callee (int i, struct box b)
+{
+ if (b.field[0])
+ return 5;
+ return i * i;
+}
+
+int __attribute__((noinline,noclone,noipa))
+test_2_caller (int i)
+{
+ struct box b;
+ [[gnu::musttail]] return test_2_callee (i + 1, b); /* { dg-error "cannot tail-call: " } */
+}
+
+extern void setjmp (void);
+void
+test_3 (void)
+{
+ [[gnu::musttail]] return setjmp (); /* { dg-error "cannot tail-call: " } */
+}
+
+typedef void (fn_ptr_t) (void);
+volatile fn_ptr_t fn_ptr;
+
+void
+test_5 (void)
+{
+ [[gnu::musttail]] return fn_ptr (); /* { dg-error "cannot tail-call: " } */
+}
new file mode 100644
@@ -0,0 +1,29 @@
+/* { dg-do compile { target { tail_call && { c || c++11 } } } } */
+
+extern int foo2 (int x, ...);
+
+struct str
+{
+ int a, b;
+};
+
+struct str
+cstruct (int x)
+{
+ if (x < 10)
+ [[clang::musttail]] return cstruct (x + 1);
+ return ((struct str){ x, 0 });
+}
+
+int
+foo (int x)
+{
+ if (x < 10)
+ [[clang::musttail]] return foo2 (x, 29);
+ if (x < 100)
+ {
+ int k = foo (x + 1);
+ [[clang::musttail]] return k; /* { dg-error "cannot tail-call: " } */
+ }
+ return x;
+}
new file mode 100644
@@ -0,0 +1,17 @@
+/* { dg-do compile { target { tail_call && { c || c++11 } } } } */
+
+struct box { char field[64]; int i; };
+
+struct box __attribute__((noinline,noclone,noipa))
+returns_struct (int i)
+{
+ struct box b;
+ b.i = i * i;
+ return b;
+}
+
+int __attribute__((noinline,noclone))
+test_1 (int i)
+{
+ [[gnu::musttail]] return returns_struct (i * 5).i; /* { dg-error "cannot tail-call: " } */
+}
new file mode 100644
@@ -0,0 +1,28 @@
+/* { dg-do compile } */
+/* { dg-options "-std=c23" { target c } } */
+/* { dg-options "-std=gnu++11" { target c++ } } */
+
+[[musttail]] int j; /* { dg-warning "attribute" } */
+__attribute__((musttail)) int k; /* { dg-warning "attribute" } */
+
+void foo(void)
+{
+ [[gnu::musttail]] j++; /* { dg-warning "attribute" } */
+ [[gnu::musttail]] if (k > 0) /* { dg-warning "attribute" } */
+ [[gnu::musttail]] k++; /* { dg-warning "attribute" } */
+}
+
+int foo2(int p)
+{
+ [[gnu::musttail(1)]] return foo2(p + 1); /* { dg-error "attribute" } */
+}
+
+int i;
+
+int foo3(void)
+{
+ [[musttail]] i++; /* { dg-warning "attribute" } */
+ [[musttail]] if (i > 10) /* { dg-warning "attribute" } */
+ [[musttail]] return foo2(i); /* { dg-warning "attribute" } */
+ return 0;
+}