Similar to Solaris, libucontext does not clear the stack below makecontext.
This causes the Go frontend to sometimes go below the stack.
On 32-bit Arm systems, this resulted in #832. It is likely, though not known,
that this could have caused other issues we've seen in gccgo as well.
Additionally, since we strip libgo.so, filename is always NULL. This caused
the unwinder to continue through runtime_mstart which caused the same issue.
--- gcc-8.5.0/libgo/runtime/go-callers.c.old 2023-01-01 17:56:27.302982459 -0600
+++ gcc-8.5.0/libgo/runtime/go-callers.c 2023-01-01 17:58:00.612903483 -0600
@@ -165,26 +165,11 @@
if (function != NULL)
{
- if (__builtin_strcmp (function, "makecontext") == 0)
+ if (__builtin_strcmp (function, "makecontext") == 0
+ || __builtin_strcmp (function, "libucontext_makecontext") == 0
+ || __builtin_strcmp (function, "runtime_mstart") == 0
+ || __builtin_strcmp (function, "runtime.kickoff") == 0
+ || __builtin_strcmp (function, "runtime.main") == 0)
return 1;
- if (filename != NULL)
- {
- const char *p;
-
- p = strrchr (filename, '/');
- if (p == NULL)
- p = filename;
- if (__builtin_strcmp (p, "/proc.c") == 0)
- {
- if (__builtin_strcmp (function, "runtime_mstart") == 0)
- return 1;
- }
- else if (__builtin_strcmp (p, "/proc.go") == 0)
- {
- if (__builtin_strcmp (function, "runtime.kickoff") == 0
- || __builtin_strcmp (function, "runtime.main") == 0)
- return 1;
- }
- }
}
return arg->index >= arg->max;
