This avoids crashes with __builtin_next_arg on non-parameters. For
the specific testcase we arrive with an anonymous SSA_NAME so that
SSA_NAME_VAR becomes NULL and we crash.
Bootstrapped and tested on x86_64-unknown-linux-gnu, pushed.
2021-02-24 Richard Biener <rguent...@suse.de>
PR c/99224
* builtins.c (fold_builtin_next_arg): Avoid NULL arg.
* gcc.dg/pr99224.c: New testcase.
---
gcc/builtins.c | 3 ++-
gcc/testsuite/gcc.dg/pr99224.c | 6 ++++++
2 files changed, 8 insertions(+), 1 deletion(-)
create mode 100644 gcc/testsuite/gcc.dg/pr99224.c
diff --git a/gcc/builtins.c b/gcc/builtins.c
index 0aed008687c..42150cee0bd 100644
--- a/gcc/builtins.c
+++ b/gcc/builtins.c
@@ -12597,7 +12597,8 @@ fold_builtin_next_arg (tree exp, bool va_start_p)
arg = CALL_EXPR_ARG (exp, 0);
}
- if (TREE_CODE (arg) == SSA_NAME)
+ if (TREE_CODE (arg) == SSA_NAME
+ && SSA_NAME_VAR (arg))
arg = SSA_NAME_VAR (arg);
/* We destructively modify the call to be __builtin_va_start (ap, 0)
diff --git a/gcc/testsuite/gcc.dg/pr99224.c b/gcc/testsuite/gcc.dg/pr99224.c
new file mode 100644
index 00000000000..f6e9ac8eba3
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr99224.c
@@ -0,0 +1,6 @@
+/* { dg-do compile } */
+
+void f (char *c, ...)
+{
+ __builtin_next_arg (*c); /* { dg-warning "not last named argument" } */
+}
--
2.26.2
