As discussed in the PR, the problem with this test case:
typedef int A[];
struct S { int i; A a; };
is twofold. Firstly, we ICE with checking on, and secondly, we reject the
testcase. But there's nothing wrong with using typedef name as a flexible
array member.
Turned out the problem was that we weren't setting a TYPE_DOMAIN for array
types in FIELD context (in case of using a typedef name) - and finish_decl
then crashed trying to determine the size of the array from initialization.
Fixed by doing what we do for normal flexible array members - that is, set
the open-ended range.
Since we had no testing for such cases whatsoever, I took existing flexible
array member tests and duplicated them, only adjusted them to use a typedef
name, so that we test as many scenarios as possible - I think this ought to
give us a reasonable level of confidence that this works as expected now.
Bootstrapped/regtested on {ppc64,x86_64}-linux, ok for trunk?
2015-02-13 Marek Polacek <pola...@redhat.com>
PR c/64768
* c-decl.c (grokdeclarator): Set the range of a flexible array member
declared through a typedef name.
* gcc.dg/array-11.c: New test.
* gcc.dg/array-12.c: New test.
* gcc.dg/array-13.c: New test.
* gcc.dg/array-14.c: New test.
* gcc.dg/c99-flex-array-typedef-1.c: New test.
* gcc.dg/c99-flex-array-typedef-2.c: New test.
* gcc.dg/c99-flex-array-typedef-3.c: New test.
* gcc.dg/c99-flex-array-typedef-5.c: New test.
* gcc.dg/c99-flex-array-typedef-7.c: New test.
* gcc.dg/c99-flex-array-typedef-8.c: New test.
diff --git gcc/c/c-decl.c gcc/c/c-decl.c
index 48c2bcb..14cf168 100644
--- gcc/c/c-decl.c
+++ gcc/c/c-decl.c
@@ -6514,6 +6514,19 @@ grokdeclarator (const struct c_declarator *declarator,
error_at (loc, "unnamed field has incomplete type");
type = error_mark_node;
}
+ else if (TREE_CODE (type) == ARRAY_TYPE
+ && TYPE_DOMAIN (type) == NULL_TREE)
+ {
+ /* We have a flexible array member through a typedef.
+ Set suitable range. Whether this is a correct position
+ for a flexible array member will be determined elsewhere. */
+ if (!in_system_header_at (input_location))
+ pedwarn_c90 (loc, OPT_Wpedantic, "ISO C90 does not "
+ "support flexible array members");
+ type = build_distinct_type_copy (TYPE_MAIN_VARIANT (type));
+ TYPE_DOMAIN (type) = build_range_type (sizetype, size_zero_node,
+ NULL_TREE);
+ }
type = c_build_qualified_type (type, type_quals);
decl = build_decl (declarator->id_loc,
FIELD_DECL, declarator->u.id, type);
diff --git gcc/testsuite/gcc.dg/array-11.c gcc/testsuite/gcc.dg/array-11.c
index e69de29..dbf38ae 100644
--- gcc/testsuite/gcc.dg/array-11.c
+++ gcc/testsuite/gcc.dg/array-11.c
@@ -0,0 +1,15 @@
+/* { dg-do compile } */
+/* { dg-options "" } */
+
+/* Verify that we can't do things to get ourselves in trouble
+ with GCC's initialized flexible array member extension. */
+
+typedef int T[];
+struct f { int w; T x; };
+struct g { struct f f; };
+struct g g1 = { { 0, { } } };
+struct g g2 = { { 0, { 1 } } }; /* { dg-error "nested context" "nested" } */
+ /* { dg-message "near init" "near" { target
*-*-* } 11 } */
+struct h { int x[0]; int y; };
+struct h h1 = { { 0 }, 1 }; /* { dg-warning "excess elements" "excess" } */
+ /* { dg-message "near init" "before end" { target
*-*-* } 14 } */
diff --git gcc/testsuite/gcc.dg/array-12.c gcc/testsuite/gcc.dg/array-12.c
index e69de29..b3beed57 100644
--- gcc/testsuite/gcc.dg/array-12.c
+++ gcc/testsuite/gcc.dg/array-12.c
@@ -0,0 +1,13 @@
+/* { dg-do compile } */
+/* { dg-options "" } */
+
+/* ISO C99 flexible array members don't have a size. GCC's zero-length
+ array extension does. */
+
+typedef int T0[0];
+typedef int T[];
+struct f { int w; T0 x; } f;
+struct g { int w; T x; } g;
+
+char test_gcc[sizeof (f.x) ? -1 : 1];
+char test_iso[sizeof (g.x) ? -1 : 1]; /* { dg-error "incomplete type" "iso" }
*/
diff --git gcc/testsuite/gcc.dg/array-13.c gcc/testsuite/gcc.dg/array-13.c
index e69de29..8335b7a 100644
--- gcc/testsuite/gcc.dg/array-13.c
+++ gcc/testsuite/gcc.dg/array-13.c
@@ -0,0 +1,28 @@
+/* { dg-do run } */
+/* { dg-options "" } */
+
+/* Verify that GCC's initialized flexible array member extension
+ works properly. */
+
+extern void abort(void);
+extern void exit(int);
+
+typedef int T[];
+typedef int T0[0];
+
+struct f { int w; T x; };
+struct g { int w; T0 x; };
+
+static struct f f = { 4, { 0, 1, 2, 3 } };
+static int junk1[] = { -1, -1, -1, -1 };
+static struct g g = { 4, { 0, 1, 2, 3 } }; /* { dg-warning "(excess
elements)|(near initialization)" "" } */
+static int junk2[] = { -1, -1, -1, -1 };
+
+int main()
+{
+ int i;
+ for (i = 0; i < f.w; ++i)
+ if (f.x[i] != i)
+ abort ();
+ exit(0);
+}
diff --git gcc/testsuite/gcc.dg/array-14.c gcc/testsuite/gcc.dg/array-14.c
index e69de29..cb2a347 100644
--- gcc/testsuite/gcc.dg/array-14.c
+++ gcc/testsuite/gcc.dg/array-14.c
@@ -0,0 +1,18 @@
+/* { dg-do compile } */
+/* { dg-options "" } */
+
+/* Verify that GCC forbids non-static initialization of
+ flexible array members. */
+
+typedef char T[];
+struct str { int len; T s; };
+
+struct str a = { 2, "a" };
+
+void foo()
+{
+ static struct str b = { 2, "b" };
+ struct str c = { 2, "c" }; /* { dg-error "(non-static)|(near
initialization)" } */
+ struct str d = (struct str) { 2, "d" }; /* { dg-error "(non-static)|(near
initialization)" } */
+ struct str e = (struct str) { d.len, "e" }; /* { dg-error
"(non-static)|(initialization)" } */
+}
diff --git gcc/testsuite/gcc.dg/c99-flex-array-typedef-1.c
gcc/testsuite/gcc.dg/c99-flex-array-typedef-1.c
index e69de29..93f91f8 100644
--- gcc/testsuite/gcc.dg/c99-flex-array-typedef-1.c
+++ gcc/testsuite/gcc.dg/c99-flex-array-typedef-1.c
@@ -0,0 +1,9 @@
+/* Test for invalid uses of flexible array members. */
+/* { dg-do compile } */
+/* { dg-options "-std=iso9899:1999 -pedantic-errors" } */
+
+typedef int A[];
+struct s1 { A x; }; /* { dg-error "empty struct" "empty" } */
+struct s2 { int :1; A x; }; /* { dg-error "empty struct" "empty" } */
+struct s3 { A x; int y; }; /* { dg-error "not at end" "not at end" } */
+struct s4 { int x; A y; };
diff --git gcc/testsuite/gcc.dg/c99-flex-array-typedef-2.c
gcc/testsuite/gcc.dg/c99-flex-array-typedef-2.c
index e69de29..f869f75 100644
--- gcc/testsuite/gcc.dg/c99-flex-array-typedef-2.c
+++ gcc/testsuite/gcc.dg/c99-flex-array-typedef-2.c
@@ -0,0 +1,17 @@
+/* Test for invalid uses of flexible array members. */
+/* { dg-do compile } */
+/* { dg-options "-std=iso9899:1999 -pedantic-errors" } */
+
+typedef char A[];
+
+struct S {
+ int n;
+ A a;
+};
+
+void
+foo (void)
+{
+ struct S s;
+ s.a = "abc"; /* { dg-error "invalid use of flexible array member" } */
+}
diff --git gcc/testsuite/gcc.dg/c99-flex-array-typedef-3.c
gcc/testsuite/gcc.dg/c99-flex-array-typedef-3.c
index e69de29..5442b6a 100644
--- gcc/testsuite/gcc.dg/c99-flex-array-typedef-3.c
+++ gcc/testsuite/gcc.dg/c99-flex-array-typedef-3.c
@@ -0,0 +1,47 @@
+/* Test for flexible array members. Test for where structures with
+ such members may not occur. */
+/* { dg-do compile } */
+/* { dg-options "-std=iso9899:1999 -pedantic-errors" } */
+
+typedef int T[];
+struct flex { int a; T b; };
+union rf1 { struct flex a; int b; };
+union rf2 { int a; struct flex b; };
+union rf3 { int a; union rf1 b; };
+union rf4 { union rf2 a; int b; };
+
+/* The above structure and unions may not be members of structures or
+ elements of arrays (6.7.2.1#2). */
+
+struct t0 { struct flex a; }; /* { dg-bogus "warning" "warning in place of
error" } */
+/* { dg-error "invalid use of structure" "struct in struct" { target *-*-* }
16 } */
+struct t1 { union rf1 a; }; /* { dg-bogus "warning" "warning in place of
error" } */
+/* { dg-error "invalid use of structure" "union in struct" { target *-*-* } 18
} */
+struct t2 { union rf2 a; }; /* { dg-bogus "warning" "warning in place of
error" } */
+/* { dg-error "invalid use of structure" "union in struct" { target *-*-* } 20
} */
+struct t3 { union rf3 a; }; /* { dg-bogus "warning" "warning in place of
error" } */
+/* { dg-error "invalid use of structure" "recursive union in struct" { target
*-*-* } 22 } */
+struct t4 { union rf4 a; }; /* { dg-bogus "warning" "warning in place of
error" } */
+/* { dg-error "invalid use of structure" "recursive union in struct" { target
*-*-* } 24 } */
+
+void f0 (struct flex[]); /* { dg-bogus "warning" "warning in place of error" }
*/
+/* { dg-error "invalid use of structure" "struct in array" { target *-*-* } 27
} */
+void f1 (union rf1[]); /* { dg-bogus "warning" "warning in place of error" } */
+/* { dg-error "invalid use of structure" "union in array" { target *-*-* } 29
} */
+void f2 (union rf2[]); /* { dg-bogus "warning" "warning in place of error" } */
+/* { dg-error "invalid use of structure" "union in array" { target *-*-* } 31
} */
+void f3 (union rf3[]); /* { dg-bogus "warning" "warning in place of error" } */
+/* { dg-error "invalid use of structure" "recursive union in array" { target
*-*-* } 33 } */
+void f4 (union rf4[]); /* { dg-bogus "warning" "warning in place of error" } */
+/* { dg-error "invalid use of structure" "recursive union in array" { target
*-*-* } 35 } */
+
+struct flex a0[1]; /* { dg-bogus "warning" "warning in place of error" } */
+/* { dg-error "invalid use of structure" "struct in array" { target *-*-* } 38
} */
+union rf1 a1[1]; /* { dg-bogus "warning" "warning in place of error" } */
+/* { dg-error "invalid use of structure" "union in array" { target *-*-* } 40
} */
+union rf2 a2[1]; /* { dg-bogus "warning" "warning in place of error" } */
+/* { dg-error "invalid use of structure" "union in array" { target *-*-* } 42
} */
+union rf3 a3[1]; /* { dg-bogus "warning" "warning in place of error" } */
+/* { dg-error "invalid use of structure" "recursive union in array" { target
*-*-* } 44 } */
+union rf4 a4[1]; /* { dg-bogus "warning" "warning in place of error" } */
+/* { dg-error "invalid use of structure" "recursive union in array" { target
*-*-* } 46 } */
diff --git gcc/testsuite/gcc.dg/c99-flex-array-typedef-5.c
gcc/testsuite/gcc.dg/c99-flex-array-typedef-5.c
index e69de29..2d1fbe1 100644
--- gcc/testsuite/gcc.dg/c99-flex-array-typedef-5.c
+++ gcc/testsuite/gcc.dg/c99-flex-array-typedef-5.c
@@ -0,0 +1,6 @@
+/* Test for flexible array members: not permitted in unions. */
+/* { dg-do compile } */
+/* { dg-options "-std=iso9899:1999 -pedantic-errors" } */
+
+typedef char T[];
+union u { int a; T b; }; /* { dg-error "flexible array member in union" } */
diff --git gcc/testsuite/gcc.dg/c99-flex-array-typedef-7.c
gcc/testsuite/gcc.dg/c99-flex-array-typedef-7.c
index e69de29..8b954db 100644
--- gcc/testsuite/gcc.dg/c99-flex-array-typedef-7.c
+++ gcc/testsuite/gcc.dg/c99-flex-array-typedef-7.c
@@ -0,0 +1,18 @@
+/* Initialization of a flexible array member with a string constant
+ must be diagnosed. PR 37481. */
+/* { dg-do compile } */
+/* { dg-options "-std=iso9899:1999 -pedantic-errors" } */
+
+typedef char T[];
+struct s { int a; T b; };
+
+struct s a = { 0, "" }; /* { dg-error "initialization of a flexible array
member" } */
+/* { dg-message "near init" "near init" { target *-*-* } 9 } */
+struct s b = { 0, { 0 } }; /* { dg-error "initialization of a flexible array
member" } */
+/* { dg-message "near init" "near init" { target *-*-* } 11 } */
+struct s c = { 0, { } }; /* { dg-error "ISO C forbids empty initializer
braces" } */
+struct s d = { .b = "" }; /* { dg-error "initialization of a flexible array
member" } */
+/* { dg-message "near init" "near init" { target *-*-* } 14 } */
+struct s e = { .b = { 0 } }; /* { dg-error "initialization of a flexible array
member" } */
+/* { dg-message "near init" "near init" { target *-*-* } 16 } */
+struct s f = { .b = { } }; /* { dg-error "ISO C forbids empty initializer
braces" } */
diff --git gcc/testsuite/gcc.dg/c99-flex-array-typedef-8.c
gcc/testsuite/gcc.dg/c99-flex-array-typedef-8.c
index e69de29..26c4a23 100644
--- gcc/testsuite/gcc.dg/c99-flex-array-typedef-8.c
+++ gcc/testsuite/gcc.dg/c99-flex-array-typedef-8.c
@@ -0,0 +1,16 @@
+/* { dg-do compile } */
+/* { dg-options "" } */
+
+typedef char T[];
+struct foo { int x; T y; };
+struct bar { struct foo f; };
+struct baz { struct bar b; };
+
+struct foo a1 = { 1, "abc" };
+struct foo a2 = { 1, { "abc" } };
+struct foo b1[] = { { 1, "abc" } }; /* { dg-error "initialization of flexible
array member" } */
+struct foo b2[] = { { 1, { "abc" } } }; /* { dg-error "initialization of
flexible array member" } */
+struct bar c1[] = { { { 1, "abc" } } }; /* { dg-error "initialization of
flexible array member" } */
+struct bar c2[] = { { { 1, { "abc" } } } }; /* { dg-error "initialization of
flexible array member" } */
+struct baz d1[] = { { { { 1, "abc" } } } }; /* { dg-error "initialization of
flexible array member" } */
+struct baz d2[] = { { { { 1, { "abc" } } } } }; /* { dg-error "initialization
of flexible array member" } */
Marek
