[PATCH v3] diagnostics: Follow DECL_ORIGIN in lhd_print_error_function [PR102061]

[Peter Damianov]

Currently, if a warning references a cloned function, the name of the cloned
function will be emitted in the "In function 'xyz'" part of the diagnostic,
which users aren't supposed to see. This patch follows the DECL_ORIGIN link
to get the name of the original function, so the internal compiler details
aren't exposed.

gcc/ChangeLog:
        PR diagnostics/102061
        * langhooks.cc (lhd_print_error_function): Follow DECL_ORIGIN
        links.
        * gcc.dg/pr102061.c: New testcase.

Signed-off-by: Peter Damianov <peter0...@disroot.org>
---
v3: also follow DECL_ORIGIN when emitting "inlined from" warnings, I missed 
this before.
Add testcase.

 gcc/langhooks.cc                |  3 +++
 gcc/testsuite/gcc.dg/pr102061.c | 35 +++++++++++++++++++++++++++++++++
 2 files changed, 38 insertions(+)
 create mode 100644 gcc/testsuite/gcc.dg/pr102061.c

diff --git a/gcc/langhooks.cc b/gcc/langhooks.cc
index 61f2b676256..7a2a66b3c39 100644
--- a/gcc/langhooks.cc
+++ b/gcc/langhooks.cc
@@ -395,6 +395,8 @@ lhd_print_error_function (diagnostic_context *context, 
const char *file,
          else
            fndecl = current_function_decl;
 
+         fndecl = DECL_ORIGIN(fndecl);
+
          if (TREE_CODE (TREE_TYPE (fndecl)) == METHOD_TYPE)
            pp_printf
              (context->printer, _("In member function %qs"),
@@ -439,6 +441,7 @@ lhd_print_error_function (diagnostic_context *context, 
const char *file,
                }
              if (fndecl)
                {
+                 fndecl = DECL_ORIGIN(fndecl);
                  expanded_location s = expand_location (*locus);
                  pp_comma (context->printer);
                  pp_newline (context->printer);
diff --git a/gcc/testsuite/gcc.dg/pr102061.c b/gcc/testsuite/gcc.dg/pr102061.c
new file mode 100644
index 00000000000..dbdd23965e7
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr102061.c
@@ -0,0 +1,35 @@
+/* { dg-do compile } */
+/* { dg-options "-Wall -O2" } */
+/* { dg-message "inlined from 'bar'" "" { target *-*-* } 0 } */
+/* { dg-excess-errors "" } */
+
+static inline void
+foo (char *p)
+{
+  __builtin___memcpy_chk (p, "abc", 3, __builtin_object_size (p, 0));
+}
+static void
+bar (char *p) __attribute__((noinline));
+static void
+bar (char *p)
+{
+  foo (p);
+}
+void f(char*) __attribute__((noipa));
+char buf[2];
+void
+baz (void) __attribute__((noinline));
+void
+baz (void)
+{
+  bar (buf);
+  f(buf);
+}
+
+void f(char*)
+{}
+
+int main(void)
+{
+    baz();
+}
-- 
2.39.2