Fix inliner ICE on alias with flatten attribute [PR92372]

gcc/ChangeLog:

2020-03-19  Jan Hubicka  <hubicka@ucw.cz>

	PR ipa/92372
	* cgraphunit.c (process_function_and_variable_attributes): warn
	for flatten attribute on alias.
	* ipa-inline.c (ipa_inline): Do not ICE on flatten attribute on alias.

gcc/testsuite/ChangeLog:

2020-03-19  Jan Hubicka  <hubicka@ucw.cz>

	PR ipa/92372
	* gcc.c-torture/pr92372.c: New test.
	* gcc.dg/attr-flatten-1.c: New test.

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 6b1b295..e1a778d 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,10 @@
+2020-03-19  Jan Hubicka  <hubicka@ucw.cz>
+
+       PR ipa/92372
+       * cgraphunit.c (process_function_and_variable_attributes): warn
+       for flatten attribute on alias.
+       * ipa-inline.c (ipa_inline): Do not ICE on flatten attribute on alias.
+
 2020-03-19  Martin Liska  <mliska@suse.cz>
 
        * lto-section-in.c: Add ext_symtab.

diff --git a/gcc/cgraphunit.c b/gcc/cgraphunit.c
index fd58636..d7ed405 100644 (file)
--- a/gcc/cgraphunit.c
+++ b/gcc/cgraphunit.c
@@ -851,6 +851,14 @@ process_function_and_variable_attributes (cgraph_node *first,
        node = symtab->next_function (node))
     {
       tree decl = node->decl;
+
+      if (node->alias
+         && lookup_attribute ("flatten", DECL_ATTRIBUTES (decl)))
+       {
+         warning_at (DECL_SOURCE_LOCATION (node->decl), OPT_Wattributes,
+                     "%<flatten%>"
+                     " attribute attribute is ignored on aliases");
+       }
       if (DECL_PRESERVE_P (decl))
        node->mark_force_output ();
       else if (lookup_attribute ("externally_visible", DECL_ATTRIBUTES (decl)))

diff --git a/gcc/ipa-inline.c b/gcc/ipa-inline.c
index 6b6ba9a..302ce16 100644 (file)
--- a/gcc/ipa-inline.c
+++ b/gcc/ipa-inline.c
@@ -2634,6 +2634,9 @@ ipa_inline (void)
     {
       node = order[i];
       if (node->definition
+         /* Do not try to flatten aliases.  These may happen for example when
+            creating local aliases.  */
+         && !node->alias
          && lookup_attribute ("flatten",
                               DECL_ATTRIBUTES (node->decl)) != NULL)
        order[j--] = order[i];

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 58f2e7e..cce1603 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,9 @@
+2020-03-19  Jan Hubicka  <hubicka@ucw.cz>
+
+       PR ipa/92372
+       * gcc.c-torture/pr92372.c: New test.
+       * gcc.dg/attr-flatten-1.c: New test.
+
 2020-03-19  Jakub Jelinek  <jakub@redhat.com>
 
        PR tree-optimization/94211

diff --git a/gcc/testsuite/gcc.c-torture/pr92372.c b/gcc/testsuite/gcc.c-torture/pr92372.c
new file mode 100644 (file)
index 0000000..72a13bb
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/pr92372.c
@@ -0,0 +1,16 @@
+int fn2(int);
+int fn3(int);
+
+__attribute__((flatten))
+int fn1(int p1)
+{
+  int a = fn2(p1);
+  return fn3(a);
+}
+__attribute__((flatten))
+int fn4(int p1)
+{
+  int j = fn2(p1);
+  return fn3(j);
+}
+

diff --git a/gcc/testsuite/gcc.dg/attr-flatten-1.c b/gcc/testsuite/gcc.dg/attr-flatten-1.c
new file mode 100644 (file)
index 0000000..ecb08fc
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/attr-flatten-1.c
@@ -0,0 +1,18 @@
+/* { dg-require-alias "" } */
+int fn2(int);
+int fn3(int);
+
+__attribute__((flatten))
+int fn1(int p1)
+{
+  int a = fn2(p1);
+  return fn3(a);
+}
+__attribute__((flatten))
+__attribute__((alias("fn1")))
+int fn4(int p1); /* { dg-warning "ignored" } */
+int
+test ()
+{
+  return fn4(1);
+}