From df90f070378583f295dd972db4400f324752a240 Mon Sep 17 00:00:00 2001
From: Martin Sebor <msebor@redhat.com>
Date: Fri, 20 Nov 2020 13:44:57 -0700
Subject: [PATCH] PR middle-end/97879 - ICE on invalid mode in attribute access
gcc/c-family/ChangeLog:
PR middle-end/97879
* c-attribs.c (handle_access_attribute): Handle ATTR_FLAG_INTERNAL.
Error out on invalid modes.
gcc/c/ChangeLog:
PR middle-end/97879
* c-decl.c (start_function): Set ATTR_FLAG_INTERNAL in flags.
gcc/ChangeLog:
PR middle-end/97879
* tree-core.h (enum attribute_flags): Add ATTR_FLAG_INTERNAL.
gcc/testsuite/ChangeLog:
PR middle-end/97879
* gcc.dg/attr-access-3.c: New test.
---
gcc/c-family/c-attribs.c | 35 +++++++++++++++++++---------
gcc/c/c-decl.c | 3 ++-
gcc/testsuite/gcc.dg/attr-access-3.c | 21 +++++++++++++++++
gcc/tree-core.h | 5 +++-
4 files changed, 51 insertions(+), 13 deletions(-)
create mode 100644 gcc/testsuite/gcc.dg/attr-access-3.c
diff --git a/gcc/c-family/c-attribs.c b/gcc/c-family/c-attribs.c
index b979fbcc0c6c..1d2ab7c81eda 100644
--- a/gcc/c-family/c-attribs.c
+++ b/gcc/c-family/c-attribs.c
@@ -2810,9 +2810,11 @@ handle_copy_attribute (tree *node, tree name, tree args,
tree attrs = TYPE_ATTRIBUTES (reftype);
/* Copy type attributes from REF to DECL. Pass in REF if it's a DECL
- or a type but not if it's an expression. */
+ or a type but not if it's an expression. Set ATTR_FLAG_INTERNAL
+ since the attributes' arguments may be in their internal form. */
for (tree at = attrs; at; at = TREE_CHAIN (at))
- decl_attributes (node, at, flags, EXPR_P (ref) ? NULL_TREE : ref);
+ decl_attributes (node, at, flags | ATTR_FLAG_INTERNAL,
+ EXPR_P (ref) ? NULL_TREE : ref);
return NULL_TREE;
}
@@ -4289,8 +4291,8 @@ append_access_attr (tree node[3], tree attrs, const char *attrstr,
the attribute and its arguments into a string. */
static tree
-handle_access_attribute (tree node[3], tree name, tree args,
- int ARG_UNUSED (flags), bool *no_add_attrs)
+handle_access_attribute (tree node[3], tree name, tree args, int flags,
+ bool *no_add_attrs)
{
tree attrs = TYPE_ATTRIBUTES (*node);
tree type = *node;
@@ -4336,15 +4338,19 @@ handle_access_attribute (tree node[3], tree name, tree args,
/* Recursively call self to "replace" the documented/external
form of the attribute with the condensend internal form. */
- decl_attributes (node, axsat, flags);
+ decl_attributes (node, axsat, flags | ATTR_FLAG_INTERNAL);
return NULL_TREE;
}
- /* This is a recursive call to handle the condensed internal form
- of the attribute (see below). Since all validation has been
- done simply return here, accepting the attribute as is. */
- *no_add_attrs = false;
- return NULL_TREE;
+ if (flags & ATTR_FLAG_INTERNAL)
+ {
+ /* This is a recursive call to handle the condensed internal
+ form of the attribute (see below). Since all validation
+ has been done simply return here, accepting the attribute
+ as is. */
+ *no_add_attrs = false;
+ return NULL_TREE;
+ }
}
/* Set to true when the access mode has the form of a function call
@@ -4363,6 +4369,13 @@ handle_access_attribute (tree node[3], tree name, tree args,
access_mode = DECL_NAME (access_mode);
funcall = true;
}
+ else if (TREE_CODE (access_mode) != IDENTIFIER_NODE)
+ {
+ error ("attribute %qE mode %qE is not an identifier; expected one of "
+ "%qs, %qs, %qs, or %qs", name, access_mode,
+ "read_only", "read_write", "write_only", "none");
+ return NULL_TREE;
+ }
const char* const access_str = IDENTIFIER_POINTER (access_mode);
const char *ps = access_str;
@@ -4573,7 +4586,7 @@ handle_access_attribute (tree node[3], tree name, tree args,
/* Recursively call self to "replace" the documented/external form
of the attribute with the condensed internal form. */
- decl_attributes (node, new_attrs, flags);
+ decl_attributes (node, new_attrs, flags | ATTR_FLAG_INTERNAL);
return NULL_TREE;
}
diff --git a/gcc/c/c-decl.c b/gcc/c/c-decl.c
index 1b02240114b8..27f77224ea47 100644
--- a/gcc/c/c-decl.c
+++ b/gcc/c/c-decl.c
@@ -9598,7 +9598,8 @@ start_function (struct c_declspecs *declspecs, struct c_declarator *declarator,
current_function_decl = pushdecl (decl1);
if (tree access = build_attr_access_from_parms (parms, false))
- decl_attributes (¤t_function_decl, access, 0, old_decl);
+ decl_attributes (¤t_function_decl, access, ATTR_FLAG_INTERNAL,
+ old_decl);
push_scope ();
declare_parm_level ();
diff --git a/gcc/testsuite/gcc.dg/attr-access-3.c b/gcc/testsuite/gcc.dg/attr-access-3.c
new file mode 100644
index 000000000000..45dd1aaad11b
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/attr-access-3.c
@@ -0,0 +1,21 @@
+/* PR middle-end/97879 - ICE on invalid mode in attribute access
+ { dg-do compile }
+ { dg-options "-Wall" } */
+
+#define A(...) __attribute__ ((access (__VA_ARGS__)))
+
+A (" ", 1) void f1 (int *); // { dg-error "attribute 'access' mode '\" \"' is not an identifier; expected one of 'read_only', 'read_write', 'write_only', or 'none'" }
+ void f1 (int *);
+
+
+A ("none", 1) void f2 (char *); // { dg-error "not an identifier" }
+ void f2 (char *);
+
+A (1) void f3 (); // { dg-error "not an identifier" }
+
+A (1, 2) void f4 (); // { dg-error "not an identifier" }
+A (2., 3.) void f5 (); // { dg-error "not an identifier" }
+
+// Verify that copying a valid access attribute doesn't cause errors.
+A (read_only, 1, 2) void f6 (void*, int);
+__attribute__ ((copy (f6))) void f7 (void*, int);
diff --git a/gcc/tree-core.h b/gcc/tree-core.h
index c9280a8d3b11..313a6af22534 100644
--- a/gcc/tree-core.h
+++ b/gcc/tree-core.h
@@ -859,7 +859,10 @@ enum attribute_flags {
are not in fact compatible with the function type. */
ATTR_FLAG_BUILT_IN = 16,
/* A given attribute has been parsed as a C++-11 attribute. */
- ATTR_FLAG_CXX11 = 32
+ ATTR_FLAG_CXX11 = 32,
+ /* The attribute handler is being invoked with an internal argument
+ that may not otherwise be valid when specified in source code. */
+ ATTR_FLAG_INTERNAL = 64
};
/* Types used to represent sizes. */
--
GitLab