From 2ddae2d57d2875e80c9186b281edfabfddb42e86 Mon Sep 17 00:00:00 2001
From: "H.J. Lu" <hjl.tools@gmail.com>
Date: Fri, 12 Jan 2018 21:12:05 -0800
Subject: [PATCH] C/C++: Add -Waddress-of-packed-member
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
When address of packed member of struct or union is taken, it may result
in an unaligned pointer value. This patch adds -Waddress-of-packed-member
to check alignment at pointer assignment and warn unaligned address as
well as unaligned pointer:
$ cat x.i
struct pair_t
{
char c;
int i;
} __attribute__ ((packed));
extern struct pair_t p;
int *addr = &p.i;
$ gcc -O2 -S x.i
x.i:8:13: warning: taking address of packed member of 'struct pair_t' may result in an unaligned pointer value [-Waddress-of-packed-member]
int *addr = &p.i;
^
$ cat c.i
struct B { int i; };
struct C { struct B b; } __attribute__ ((packed));
long* g8 (struct C *p) { return p; }
$ gcc -O2 -S c.i -Wno-incompatible-pointer-types
c.i: In function ‘g8’:
c.i:4:33: warning: returning ‘struct C *’ from a function with incompatible return type ‘long int *’ [-Wincompatible-pointer-types]
long* g8 (struct C *p) { return p; }
^
c.i:4:33: warning: converting a packed ‘struct C *’ pointer increases the alignment of ‘long int *’ pointer from 1 to 8 [-Waddress-of-packed-member]
c.i:2:8: note: defined here
struct C { struct B b; } __attribute__ ((packed));
^
$
This warning is enabled by default. Since read_encoded_value_with_base
in unwind-pe.h has
union unaligned
{
void *ptr;
unsigned u2 __attribute__ ((mode (HI)));
unsigned u4 __attribute__ ((mode (SI)));
unsigned u8 __attribute__ ((mode (DI)));
signed s2 __attribute__ ((mode (HI)));
signed s4 __attribute__ ((mode (SI)));
signed s8 __attribute__ ((mode (DI)));
} __attribute__((__packed__));
_Unwind_Internal_Ptr result;
and GCC warns:
gcc/libgcc/unwind-pe.h:210:37: warning: taking address of packed member of 'union unaligned' may result in an unaligned pointer value [-Waddress-of-packed-member]
result = (_Unwind_Internal_Ptr) u->ptr;
^
we need to add GCC pragma to ignore -Waddress-of-packed-member.
gcc/c/
PR c/51628
* doc/invoke.texi: Document -Wno-address-of-packed-member.
gcc/c-family/
PR c/51628
* c-common.h (warn_for_address_or_pointer_of_packed_member): New.
* c-warn.c (check_address_of_packed_member): New function.
(warn_for_address_or_pointer_of_packed_member): Likewise.
* c.opt: Add -Wno-address-of-packed-member.
gcc/c/
PR c/51628
* c-typeck.c (convert_for_assignment): Call
warn_for_address_or_pointer_of_packed_member.
gcc/cp/
PR c/51628
* call.c (convert_for_arg_passing): Call
warn_for_address_or_pointer_of_packed_member.
* typeck.c (convert_for_assignment): Likewise.
gcc/testsuite/
PR c/51628
* c-c++-common/pr51628-1.c: New test.
* c-c++-common/pr51628-2.c: Likewise.
* c-c++-common/pr51628-3.c: Likewise.
* c-c++-common/pr51628-4.c: Likewise.
* c-c++-common/pr51628-5.c: Likewise.
* c-c++-common/pr51628-6.c: Likewise.
* c-c++-common/pr51628-7.c: Likewise.
* c-c++-common/pr51628-8.c: Likewise.
* c-c++-common/pr51628-9.c: Likewise.
* c-c++-common/pr51628-10.c: Likewise.
* c-c++-common/pr51628-11.c: Likewise.
* c-c++-common/pr51628-12.c: Likewise.
* c-c++-common/pr51628-13.c: Likewise.
* c-c++-common/pr51628-14.c: Likewise.
* c-c++-common/pr51628-15.c: Likewise.
* c-c++-common/pr51628-26.c: Likewise.
* gcc.dg/pr51628-17.c: Likewise.
* gcc.dg/pr51628-18.c: Likewise.
* gcc.dg/pr51628-19.c: Likewise.
* gcc.dg/pr51628-20.c: Likewise.
* gcc.dg/pr51628-21.c: Likewise.
* gcc.dg/pr51628-22.c: Likewise.
* gcc.dg/pr51628-23.c: Likewise.
* gcc.dg/pr51628-24.c: Likewise.
* gcc.dg/pr51628-25.c: Likewise.
* c-c++-common/asan/misalign-1.c: Add
-Wno-address-of-packed-member.
* c-c++-common/asan/misalign-2.c: Likewise.
* c-c++-common/ubsan/align-2.c: Likewise.
* c-c++-common/ubsan/align-4.c: Likewise.
* c-c++-common/ubsan/align-6.c: Likewise.
* c-c++-common/ubsan/align-7.c: Likewise.
* c-c++-common/ubsan/align-8.c: Likewise.
* c-c++-common/ubsan/align-10.c: Likewise.
* g++.dg/ubsan/align-2.C: Likewise.
* gcc.target/i386/avx512bw-vmovdqu16-2.c: Likewise.
* gcc.target/i386/avx512f-vmovdqu32-2.c: Likewise.
* gcc.target/i386/avx512f-vmovdqu64-2.c: Likewise.
* gcc.target/i386/avx512vl-vmovdqu16-2.c: Likewise.
* gcc.target/i386/avx512vl-vmovdqu32-2.c: Likewise.
* gcc.target/i386/avx512vl-vmovdqu64-2.c: Likewise.
libgcc/
* unwind-pe.h (read_encoded_value_with_base): Add GCC pragma
to ignore -Waddress-of-packed-member.
---
gcc/c-family/c-common.h | 1 +
gcc/c-family/c-warn.c | 173 ++++++++++++++++++
gcc/c-family/c.opt | 4 +
gcc/c/c-typeck.c | 10 +-
gcc/cp/call.c | 3 +
gcc/cp/typeck.c | 2 +
gcc/doc/invoke.texi | 9 +-
gcc/testsuite/c-c++-common/asan/misalign-1.c | 2 +-
gcc/testsuite/c-c++-common/asan/misalign-2.c | 2 +-
gcc/testsuite/c-c++-common/pr51628-1.c | 29 +++
gcc/testsuite/c-c++-common/pr51628-10.c | 24 +++
gcc/testsuite/c-c++-common/pr51628-11.c | 17 ++
gcc/testsuite/c-c++-common/pr51628-12.c | 18 ++
gcc/testsuite/c-c++-common/pr51628-13.c | 9 +
gcc/testsuite/c-c++-common/pr51628-14.c | 9 +
gcc/testsuite/c-c++-common/pr51628-15.c | 14 ++
gcc/testsuite/c-c++-common/pr51628-16.c | 13 ++
gcc/testsuite/c-c++-common/pr51628-2.c | 29 +++
gcc/testsuite/c-c++-common/pr51628-26.c | 33 ++++
gcc/testsuite/c-c++-common/pr51628-3.c | 35 ++++
gcc/testsuite/c-c++-common/pr51628-4.c | 35 ++++
gcc/testsuite/c-c++-common/pr51628-5.c | 35 ++++
gcc/testsuite/c-c++-common/pr51628-6.c | 35 ++++
gcc/testsuite/c-c++-common/pr51628-7.c | 29 +++
gcc/testsuite/c-c++-common/pr51628-8.c | 36 ++++
gcc/testsuite/c-c++-common/pr51628-9.c | 36 ++++
gcc/testsuite/c-c++-common/ubsan/align-10.c | 2 +-
gcc/testsuite/c-c++-common/ubsan/align-2.c | 2 +-
gcc/testsuite/c-c++-common/ubsan/align-4.c | 2 +-
gcc/testsuite/c-c++-common/ubsan/align-6.c | 2 +-
gcc/testsuite/c-c++-common/ubsan/align-7.c | 2 +-
gcc/testsuite/c-c++-common/ubsan/align-8.c | 2 +-
gcc/testsuite/g++.dg/ubsan/align-2.C | 2 +-
gcc/testsuite/gcc.dg/pr51628-17.c | 10 +
gcc/testsuite/gcc.dg/pr51628-18.c | 23 +++
gcc/testsuite/gcc.dg/pr51628-19.c | 26 +++
gcc/testsuite/gcc.dg/pr51628-20.c | 11 ++
gcc/testsuite/gcc.dg/pr51628-21.c | 11 ++
gcc/testsuite/gcc.dg/pr51628-22.c | 9 +
gcc/testsuite/gcc.dg/pr51628-23.c | 9 +
gcc/testsuite/gcc.dg/pr51628-24.c | 10 +
gcc/testsuite/gcc.dg/pr51628-25.c | 9 +
.../gcc.target/i386/avx512bw-vmovdqu16-2.c | 2 +-
.../gcc.target/i386/avx512f-vmovdqu32-2.c | 2 +-
.../gcc.target/i386/avx512f-vmovdqu64-2.c | 2 +-
.../gcc.target/i386/avx512vl-vmovdqu16-2.c | 2 +-
.../gcc.target/i386/avx512vl-vmovdqu32-2.c | 2 +-
.../gcc.target/i386/avx512vl-vmovdqu64-2.c | 2 +-
libgcc/unwind-pe.h | 5 +
49 files changed, 774 insertions(+), 17 deletions(-)
create mode 100644 gcc/testsuite/c-c++-common/pr51628-1.c
create mode 100644 gcc/testsuite/c-c++-common/pr51628-10.c
create mode 100644 gcc/testsuite/c-c++-common/pr51628-11.c
create mode 100644 gcc/testsuite/c-c++-common/pr51628-12.c
create mode 100644 gcc/testsuite/c-c++-common/pr51628-13.c
create mode 100644 gcc/testsuite/c-c++-common/pr51628-14.c
create mode 100644 gcc/testsuite/c-c++-common/pr51628-15.c
create mode 100644 gcc/testsuite/c-c++-common/pr51628-16.c
create mode 100644 gcc/testsuite/c-c++-common/pr51628-2.c
create mode 100644 gcc/testsuite/c-c++-common/pr51628-26.c
create mode 100644 gcc/testsuite/c-c++-common/pr51628-3.c
create mode 100644 gcc/testsuite/c-c++-common/pr51628-4.c
create mode 100644 gcc/testsuite/c-c++-common/pr51628-5.c
create mode 100644 gcc/testsuite/c-c++-common/pr51628-6.c
create mode 100644 gcc/testsuite/c-c++-common/pr51628-7.c
create mode 100644 gcc/testsuite/c-c++-common/pr51628-8.c
create mode 100644 gcc/testsuite/c-c++-common/pr51628-9.c
create mode 100644 gcc/testsuite/gcc.dg/pr51628-17.c
create mode 100644 gcc/testsuite/gcc.dg/pr51628-18.c
create mode 100644 gcc/testsuite/gcc.dg/pr51628-19.c
create mode 100644 gcc/testsuite/gcc.dg/pr51628-20.c
create mode 100644 gcc/testsuite/gcc.dg/pr51628-21.c
create mode 100644 gcc/testsuite/gcc.dg/pr51628-22.c
create mode 100644 gcc/testsuite/gcc.dg/pr51628-23.c
create mode 100644 gcc/testsuite/gcc.dg/pr51628-24.c
create mode 100644 gcc/testsuite/gcc.dg/pr51628-25.c
@@ -1271,6 +1271,7 @@ extern void c_do_switch_warnings (splay_tree, location_t, tree, tree, bool,
bool);
extern void warn_for_omitted_condop (location_t, tree);
extern bool warn_for_restrict (unsigned, tree *, unsigned);
+extern void warn_for_address_or_pointer_of_packed_member (bool, tree, tree);
/* Places where an lvalue, or modifiable lvalue, may be required.
Used to select diagnostic messages in lvalue_error and
@@ -2606,3 +2606,176 @@ warn_for_multistatement_macros (location_t body_loc, location_t next_loc,
inform (guard_loc, "some parts of macro expansion are not guarded by "
"this %qs clause", guard_tinfo_to_string (keyword));
}
+
+/* Return struct or union type if the right hand value, RHS, takes the
+ unaligned address of packed member of struct or union when assigning
+ to TYPE. Otherwise, return NULL_TREE. */
+
+static tree
+check_address_of_packed_member (tree type, tree rhs)
+{
+ tree base;
+ tree object;
+ tree field;
+
+ if (INDIRECT_REF_P (rhs))
+ rhs = TREE_OPERAND (rhs, 0);
+
+ switch (TREE_CODE (rhs))
+ {
+ case ADDR_EXPR:
+ base = TREE_OPERAND (rhs, 0);
+ while (TREE_CODE (base) == ARRAY_REF)
+ base = TREE_OPERAND (base, 0);
+ if (TREE_CODE (base) != COMPONENT_REF)
+ return NULL_TREE;
+ object = TREE_OPERAND (base, 0);
+ field = TREE_OPERAND (base, 1);
+ break;
+ case COMPONENT_REF:
+ object = TREE_OPERAND (rhs, 0);
+ field = TREE_OPERAND (rhs, 1);
+ break;
+ default:
+ return NULL_TREE;
+ }
+
+ tree context;
+ unsigned int type_align, record_align;
+
+ /* Check alignment of the data member. */
+ if (TREE_CODE (field) == FIELD_DECL
+ && (DECL_PACKED (field)
+ || TYPE_PACKED (TREE_TYPE (field))))
+ {
+ /* Check the expected alignment against the field alignment. */
+ type_align = TYPE_ALIGN (type);
+ context = DECL_CONTEXT (field);
+ record_align = TYPE_ALIGN (context);
+ if ((record_align % type_align) != 0)
+ return context;
+ tree field_off = byte_position (field);
+ if (!multiple_of_p (TREE_TYPE (field_off), field_off,
+ size_int (type_align / BITS_PER_UNIT)))
+ return context;
+ }
+
+ /* Check alignment of the object. */
+ if (TREE_CODE (object) == COMPONENT_REF)
+ {
+ field = TREE_OPERAND (object, 1);
+ if (TREE_CODE (field) == FIELD_DECL && DECL_PACKED (field))
+ {
+ type_align = TYPE_ALIGN (type);
+ context = DECL_CONTEXT (field);
+ record_align = TYPE_ALIGN (context);
+ if ((record_align % type_align) != 0)
+ return context;
+ }
+ }
+
+ return NULL_TREE;
+}
+
+/* Warn if the right hand value, RHS:
+ 1. For ADDRESS_P == true, is an address which takes the unaligned
+ address of packed member of struct or union when assigning to TYPE.
+ 2. For ADDRESS_P == false, is a pointer value which isn't aligned to a
+ pointer type TYPE.
+*/
+
+void
+warn_for_address_or_pointer_of_packed_member (bool address_p, tree type,
+ tree rhs)
+{
+ if (!warn_address_of_packed_member)
+ return;
+
+ /* Don't warn if we don't assign RHS to a pointer. */
+ if (!POINTER_TYPE_P (type))
+ return;
+
+ while (TREE_CODE (rhs) == COMPOUND_EXPR)
+ rhs = TREE_OPERAND (rhs, 1);
+
+ if (address_p)
+ {
+ /* Get the type of the pointer pointing to. */
+ type = TREE_TYPE (type);
+
+ if (TREE_CODE (rhs) == NOP_EXPR)
+ rhs = TREE_OPERAND (rhs, 0);
+ }
+ else
+ {
+ bool rhspointer_p;
+ tree rhstype;
+
+ /* Check the original type of RHS. */
+ switch (TREE_CODE (rhs))
+ {
+ case PARM_DECL:
+ case VAR_DECL:
+ rhstype = TREE_TYPE (rhs);
+ rhspointer_p = POINTER_TYPE_P (rhstype);
+ break;
+ case NOP_EXPR:
+ rhs = TREE_OPERAND (rhs, 0);
+ if (TREE_CODE (rhs) == ADDR_EXPR)
+ rhs = TREE_OPERAND (rhs, 0);
+ rhstype = TREE_TYPE (rhs);
+ rhspointer_p = TREE_CODE (rhstype) == ARRAY_TYPE;
+ break;
+ default:
+ return;
+ }
+
+ if (rhspointer_p && TYPE_PACKED (TREE_TYPE (rhstype)))
+ {
+ unsigned int type_align = TYPE_ALIGN_UNIT (TREE_TYPE (type));
+ unsigned int rhs_align = TYPE_ALIGN_UNIT (TREE_TYPE (rhstype));
+ if ((rhs_align % type_align) != 0)
+ {
+ location_t location = EXPR_LOC_OR_LOC (rhs, input_location);;
+ warning_at (location, OPT_Waddress_of_packed_member,
+ "converting a packed %qT pointer increases the "
+ "alignment of %qT pointer from %d to %d",
+ rhstype, type, rhs_align, type_align);
+ tree decl = TYPE_STUB_DECL (TREE_TYPE (rhstype));
+ inform (DECL_SOURCE_LOCATION (decl), "defined here");
+ decl = TYPE_STUB_DECL (TREE_TYPE (type));
+ if (decl)
+ inform (DECL_SOURCE_LOCATION (decl), "defined here");
+ }
+ }
+ return;
+ }
+
+ tree context;
+
+ if (TREE_CODE (rhs) == COND_EXPR)
+ {
+ /* Check the THEN path first. */
+ tree op1 = TREE_OPERAND (rhs, 1);
+ context = check_address_of_packed_member (type, op1);
+ if (context)
+ rhs = op1;
+ else
+ {
+ /* Check the ELSE path. */
+ rhs = TREE_OPERAND (rhs, 2);
+ context = check_address_of_packed_member (type, rhs);
+ }
+ }
+ else
+ context = check_address_of_packed_member (type, rhs);
+
+ if (context)
+ {
+ location_t loc = EXPR_LOC_OR_LOC (rhs, input_location);
+ warning_at (loc, OPT_Waddress_of_packed_member,
+ "taking address of packed member of %qT may result "
+ "in an unaligned pointer value",
+ context);
+ }
+}
@@ -612,6 +612,10 @@ Wincompatible-pointer-types
C ObjC Var(warn_incompatible_pointer_types) Init(1) Warning
Warn when there is a conversion between pointers that have incompatible types.
+Waddress-of-packed-member
+C ObjC C++ ObjC++ Var(warn_address_of_packed_member) Init(1) Warning
+Warn when the address of packed member of struct or union is taken.
+
Winit-self
C ObjC C++ ObjC++ Var(warn_init_self) Warning LangEnabledBy(C++ ObjC++,Wall)
Warn about variables which are initialized to themselves.
@@ -6514,7 +6514,10 @@ convert_for_assignment (location_t location, location_t expr_loc, tree type,
}
if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (rhstype))
- return rhs;
+ {
+ warn_for_address_or_pointer_of_packed_member (true, type, orig_rhs);
+ return rhs;
+ }
if (coder == VOID_TYPE)
{
@@ -7001,6 +7004,11 @@ convert_for_assignment (location_t location, location_t expr_loc, tree type,
}
}
+ /* If RHS is't an address, check pointer or array of packed
+ struct or union. */
+ warn_for_address_or_pointer_of_packed_member
+ (TREE_CODE (orig_rhs) == ADDR_EXPR, type, orig_rhs);
+
return convert (type, rhs);
}
else if (codel == POINTER_TYPE && coder == ARRAY_TYPE)
@@ -7470,6 +7470,9 @@ convert_for_arg_passing (tree type, tree val, tsubst_flags_t complain)
}
maybe_warn_parm_abi (type, cp_expr_loc_or_loc (val, input_location));
}
+
+ warn_for_address_or_pointer_of_packed_member (true, type, val);
+
return val;
}
@@ -8914,6 +8914,8 @@ convert_for_assignment (tree type, tree rhs,
TREE_NO_WARNING (rhs) = 1;
}
+ warn_for_address_or_pointer_of_packed_member (true, type, rhs);
+
return perform_implicit_conversion_flags (strip_top_quals (type), rhs,
complain, flags);
}
@@ -275,7 +275,7 @@ Objective-C and Objective-C++ Dialects}.
@xref{Warning Options,,Options to Request or Suppress Warnings}.
@gccoptlist{-fsyntax-only -fmax-errors=@var{n} -Wpedantic @gol
-pedantic-errors @gol
--w -Wextra -Wall -Waddress -Waggregate-return @gol
+-w -Wextra -Wall -Waddress -Waddress-of-packed-member -Waggregate-return @gol
-Walloc-zero -Walloc-size-larger-than=@var{byte-size}
-Walloca -Walloca-larger-than=@var{byte-size} @gol
-Wno-aggressive-loop-optimizations -Warray-bounds -Warray-bounds=@var{n} @gol
@@ -6581,6 +6581,13 @@ behavior and are not portable in C, so they usually indicate that the
programmer intended to use @code{strcmp}. This warning is enabled by
@option{-Wall}.
+@item -Waddress-of-packed-member
+@opindex Waddress-of-packed-member
+@opindex Wno-address-of-packed-member
+Warn when the address of packed member of struct or union is taken,
+which usually results in an unaligned pointer value. This is
+enabled by default.
+
@item -Wlogical-op
@opindex Wlogical-op
@opindex Wno-logical-op
@@ -1,5 +1,5 @@
/* { dg-do run { target { ilp32 || lp64 } } } */
-/* { dg-skip-if "" { *-*-* } { "*" } { "-O2" } } */
+/* { dg-skip-if "" { *-*-* } { "*" } { "-O2 -Wno-address-of-packed-member" } } */
/* { dg-additional-options "-fno-omit-frame-pointer" { target *-*-darwin* } } */
/* { dg-shouldfail "asan" } */
@@ -1,5 +1,5 @@
/* { dg-do run { target { ilp32 || lp64 } } } */
-/* { dg-skip-if "" { *-*-* } { "*" } { "-O2" } } */
+/* { dg-skip-if "" { *-*-* } { "*" } { "-O2 -Wno-address-of-packed-member" } } */
/* { dg-additional-options "-fno-omit-frame-pointer" { target *-*-darwin* } } */
/* { dg-shouldfail "asan" } */
new file mode 100644
@@ -0,0 +1,29 @@
+/* PR c/51628. */
+/* { dg-do compile } */
+/* { dg-options "-O" } */
+
+struct pair_t
+{
+ int x;
+ int i;
+} __attribute__((packed, aligned (4)));
+
+extern struct pair_t p;
+extern int *x;
+extern void bar (int *);
+
+int *addr = &p.i;
+
+int *
+foo (void)
+{
+ struct pair_t arr[2] = { { 1, 10 }, { 2, 20 } };
+ int *p0, *p1;
+ p0 = &arr[0].i;
+ bar (p0);
+ p1 = &arr[1].i;
+ bar (p1);
+ bar (&p.i);
+ x = &p.i;
+ return &p.i;
+}
new file mode 100644
@@ -0,0 +1,24 @@
+/* PR c/51628. */
+/* { dg-do run { target int128 } } */
+/* { dg-options "-O2" } */
+
+struct pair_t
+{
+ char c;
+ __int128_t i;
+} __attribute__ ((packed));
+
+typedef struct unaligned_int128_t_
+{
+ __int128_t value;
+} __attribute__((packed)) unaligned_int128_t;
+
+struct pair_t p = {0, 1};
+unaligned_int128_t *addr = (unaligned_int128_t *) &p.i;
+
+int
+main()
+{
+ addr->value = ~(__int128_t)0;
+ return (p.i != 1) ? 0 : 1;
+}
new file mode 100644
@@ -0,0 +1,17 @@
+/* PR c/51628. */
+/* { dg-do compile { target int128 } } */
+/* { dg-options "-O" } */
+
+struct tuple_t
+{
+ char c[12];
+ __int128_t i;
+} __attribute__((packed, aligned (8)));
+
+typedef struct unaligned_int128_t_
+{
+ __int128_t value;
+} __attribute__ ((packed, aligned(4))) unaligned_int128_t;
+
+struct tuple_t p = {{0}, 1};
+unaligned_int128_t *addr = (unaligned_int128_t *)(&p.i);
new file mode 100644
@@ -0,0 +1,18 @@
+/* PR c/51628. */
+/* { dg-do compile { target int128 } } */
+/* { dg-options "-O" } */
+
+struct tuple_t
+{
+ char c[10];
+ __int128_t i;
+} __attribute__((packed, aligned (8)));
+
+typedef struct unaligned_int128_t_
+{
+ __int128_t value;
+} __attribute__ ((packed, aligned(4))) unaligned_int128_t;
+
+struct tuple_t p = {{0}, 1};
+unaligned_int128_t *addr = (unaligned_int128_t *)(&p.i);
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
new file mode 100644
@@ -0,0 +1,9 @@
+/* PR c/51628. */
+/* { dg-do compile } */
+/* { dg-options "-O" } */
+
+struct B { int i; };
+struct C { struct B b; } __attribute__ ((packed));
+
+int* h4 (struct C *p) { return &p->b.i; }
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
new file mode 100644
@@ -0,0 +1,9 @@
+/* PR c/51628. */
+/* { dg-do compile } */
+/* { dg-options "-O" } */
+
+struct A {
+ int i;
+} __attribute__ ((packed));
+
+void* f0 (struct A *p) { return &p->i; }
new file mode 100644
@@ -0,0 +1,14 @@
+/* PR c/51628. */
+/* { dg-do compile } */
+/* { dg-options "-O" } */
+
+struct A {
+ int i;
+} __attribute__ ((packed));
+
+int*
+f (struct A *p, int *q)
+{
+ return q ? q : &p->i;
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
+}
new file mode 100644
@@ -0,0 +1,13 @@
+/* PR c/51628. */
+/* { dg-do compile } */
+/* { dg-options "-O" } */
+
+struct __attribute__ ((packed)) A { int i; };
+struct B {
+ struct A a;
+} b;
+
+int *p = (int*)&b.a.i;
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
+int *q = (int*)&b.a;
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
new file mode 100644
@@ -0,0 +1,29 @@
+/* PR c/51628. */
+/* { dg-do compile } */
+/* { dg-options "-O" } */
+
+struct pair_t
+{
+ int x;
+ int i;
+} __attribute__((packed, aligned (8)));
+
+extern struct pair_t p;
+extern int *x;
+extern void bar (int *);
+
+int *addr = &p.i;
+
+int *
+foo (void)
+{
+ struct pair_t arr[2] = { { 1, 10 }, { 2, 20 } };
+ int *p0, *p1;
+ p0 = &arr[0].i;
+ bar (p0);
+ p1 = &arr[1].i;
+ bar (p1);
+ bar (&p.i);
+ x = &p.i;
+ return &p.i;
+}
new file mode 100644
@@ -0,0 +1,33 @@
+/* PR c/51628. */
+/* { dg-do compile } */
+/* { dg-options "-O" } */
+
+struct A {
+ int i;
+} __attribute__ ((packed));
+
+struct A p = {1};
+int *addr;
+
+int i, j;
+
+void
+foo1 (void)
+{
+ addr = (i = -1, &p.i);
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
+}
+
+void
+foo2 (void)
+{
+ addr = (i = -1, j = -2, &p.i);
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
+}
+
+void
+foo3 (void)
+{
+ addr = (i = -1, (j = -2, &p.i));
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
+}
new file mode 100644
@@ -0,0 +1,35 @@
+/* PR c/51628. */
+/* { dg-do compile } */
+/* { dg-options "-O" } */
+
+struct pair_t
+{
+ int x;
+ int i;
+} __attribute__((packed, aligned (2)));
+
+extern struct pair_t p;
+extern int *x;
+extern void bar (int *);
+
+int *addr = &p.i;
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
+
+int *
+foo (void)
+{
+ struct pair_t arr[2] = { { 1, 10 }, { 2, 20 } };
+ int *p0, *p1;
+ p0 = &arr[0].i;
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
+ bar (p0);
+ p1 = &arr[1].i;
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
+ bar (p1);
+ bar (&p.i);
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
+ x = &p.i;
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
+ return &p.i;
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
+}
new file mode 100644
@@ -0,0 +1,35 @@
+/* PR c/51628. */
+/* { dg-do compile } */
+/* { dg-options "-O" } */
+
+struct pair_t
+{
+ int x;
+ int i;
+} __attribute__((packed));
+
+extern struct pair_t p;
+extern int *x;
+extern void bar (int *);
+
+int *addr = &p.i;
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
+
+int *
+foo (void)
+{
+ struct pair_t arr[2] = { { 1, 10 }, { 2, 20 } };
+ int *p0, *p1;
+ p0 = &arr[0].i;
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
+ bar (p0);
+ p1 = &arr[1].i;
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
+ bar (p1);
+ bar (&p.i);
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
+ x = &p.i;
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
+ return &p.i;
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
+}
new file mode 100644
@@ -0,0 +1,35 @@
+/* PR c/51628. */
+/* { dg-do compile } */
+/* { dg-options "-O" } */
+
+struct pair_t
+{
+ char x;
+ int i;
+} __attribute__((packed));
+
+extern struct pair_t p;
+extern int *x;
+extern void bar (int *);
+
+int *addr = &p.i;
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
+
+int *
+foo (void)
+{
+ struct pair_t arr[2] = { { 1, 10 }, { 2, 20 } };
+ int *p0, *p1;
+ p0 = &arr[0].i;
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
+ bar (p0);
+ p1 = &arr[1].i;
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
+ bar (p1);
+ bar (&p.i);
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
+ x = &p.i;
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
+ return &p.i;
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
+}
new file mode 100644
@@ -0,0 +1,35 @@
+/* PR c/51628. */
+/* { dg-do compile } */
+/* { dg-options "-O" } */
+
+struct pair_t
+{
+ char x;
+ int i;
+} __attribute__((packed, aligned (4)));
+
+extern struct pair_t p;
+extern int *x;
+extern void bar (int *);
+
+int *addr = &p.i;
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
+
+int *
+foo (void)
+{
+ struct pair_t arr[2] = { { 1, 10 }, { 2, 20 } };
+ int *p0, *p1;
+ p0 = &arr[0].i;
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
+ bar (p0);
+ p1 = &arr[1].i;
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
+ bar (p1);
+ bar (&p.i);
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
+ x = &p.i;
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
+ return &p.i;
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
+}
new file mode 100644
@@ -0,0 +1,29 @@
+/* PR c/51628. */
+/* { dg-do compile } */
+/* { dg-options "-O" } */
+
+struct pair_t
+{
+ int x;
+ int i[4];
+} __attribute__((packed, aligned (4)));
+
+extern struct pair_t p;
+extern int *x;
+extern void bar (int *);
+
+int *addr = p.i;
+
+int *
+foo (struct pair_t *p)
+{
+ int *p0, *p1;
+ p0 = p->i;
+ bar (p0);
+ p1 = &p->i[1];
+ bar (p1);
+ bar (p->i);
+ bar (&p->i[2]);
+ x = p->i;
+ return &p->i[3];
+}
new file mode 100644
@@ -0,0 +1,36 @@
+/* PR c/51628. */
+/* { dg-do compile } */
+/* { dg-options "-O" } */
+
+struct pair_t
+{
+ char x;
+ int i[4];
+} __attribute__ ((packed, aligned (4)));
+
+extern struct pair_t p;
+extern int *x;
+extern void bar (int *);
+
+int *addr = p.i;
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
+
+int *
+foo (struct pair_t *p)
+{
+ int *p0, *p1;
+ p0 = p->i;
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
+ bar (p0);
+ p1 = &p->i[1];
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
+ bar (p1);
+ bar (p->i);
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
+ bar (&p->i[2]);
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
+ x = p->i;
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
+ return &p->i[3];
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
+}
new file mode 100644
@@ -0,0 +1,36 @@
+/* PR c/51628. */
+/* { dg-do compile } */
+/* { dg-options "-O" } */
+
+struct pair_t
+{
+ int x;
+ int i[4];
+} __attribute__ ((packed));
+
+extern struct pair_t p;
+extern int *x;
+extern void bar (int *);
+
+int *addr = p.i;
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
+
+int *
+foo (struct pair_t *p)
+{
+ int *p0, *p1;
+ p0 = p->i;
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
+ bar (p0);
+ p1 = &p->i[1];
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
+ bar (p1);
+ bar (p->i);
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
+ bar (&p->i[2]);
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
+ x = p->i;
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
+ return &p->i[3];
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
+}
@@ -1,6 +1,6 @@
/* Limit this to known non-strict alignment targets. */
/* { dg-do run { target { i?86-*-linux* x86_64-*-linux* } } } */
-/* { dg-options "-O -fsanitize=alignment -fsanitize-recover=alignment" } */
+/* { dg-options "-O -fsanitize=alignment -fsanitize-recover=alignment -Wno-address-of-packed-member" } */
struct R { int a; } r;
struct S { struct R a; char b; long long c; short d[10]; };
@@ -1,6 +1,6 @@
/* Limit this to known non-strict alignment targets. */
/* { dg-do run { target { i?86-*-linux* x86_64-*-linux* } } } */
-/* { dg-options "-fsanitize=alignment" } */
+/* { dg-options "-fsanitize=alignment -Wno-address-of-packed-member" } */
struct S { int a; char b; long long c; short d[10]; };
struct T { char a; long long b; };
@@ -1,6 +1,6 @@
/* Limit this to known non-strict alignment targets. */
/* { dg-do run { target { i?86-*-linux* x86_64-*-linux* } } } */
-/* { dg-options "-fsanitize=null,alignment" } */
+/* { dg-options "-fsanitize=null,alignment -Wno-address-of-packed-member" } */
#include "align-2.c"
@@ -1,6 +1,6 @@
/* Limit this to known non-strict alignment targets. */
/* { dg-do run { target { i?86-*-linux* x86_64-*-linux* } } } */
-/* { dg-options "-O -fsanitize=alignment -fsanitize-recover=alignment" } */
+/* { dg-options "-O -fsanitize=alignment -fsanitize-recover=alignment -Wno-address-of-packed-member" } */
struct S { int a; char b; long long c; short d[10]; };
struct T { char a; long long b; };
@@ -1,6 +1,6 @@
/* Limit this to known non-strict alignment targets. */
/* { dg-do run { target { i?86-*-linux* x86_64-*-linux* } } } */
-/* { dg-options "-O -fsanitize=alignment -fno-sanitize-recover=alignment -fdump-tree-sanopt-details" } */
+/* { dg-options "-O -fsanitize=alignment -fno-sanitize-recover=alignment -Wno-address-of-packed-member -fdump-tree-sanopt-details" } */
/* { dg-skip-if "" { *-*-* } { "-flto -fno-fat-lto-objects" } } */
/* { dg-shouldfail "ubsan" } */
@@ -1,6 +1,6 @@
/* Limit this to known non-strict alignment targets. */
/* { dg-do run { target { i?86-*-linux* x86_64-*-linux* } } } */
-/* { dg-options "-O -fsanitize=alignment -fsanitize-undefined-trap-on-error -fdump-tree-sanopt-details" } */
+/* { dg-options "-O -fsanitize=alignment -fsanitize-undefined-trap-on-error -Wno-address-of-packed-member -fdump-tree-sanopt-details" } */
/* { dg-skip-if "" { *-*-* } { "-flto -fno-fat-lto-objects" } } */
/* { dg-shouldfail "ubsan" } */
@@ -1,6 +1,6 @@
// Limit this to known non-strict alignment targets.
// { dg-do run { target { i?86-*-linux* x86_64-*-linux* } } }
-// { dg-options "-fsanitize=alignment -Wall -Wno-unused-variable -std=c++11" }
+// { dg-options "-fsanitize=alignment -Wall -Wno-unused-variable -Wno-address-of-packed-member -std=c++11" }
typedef const long int L;
struct S { long int l; char buf[1 + sizeof (int) + sizeof (L)]; } s;
new file mode 100644
@@ -0,0 +1,10 @@
+/* PR c/51628. */
+/* { dg-do compile } */
+/* { dg-options "-O -Wno-incompatible-pointer-types" } */
+
+struct A {
+ int i;
+} __attribute__ ((packed));
+
+long* f8 (struct A *p) { return &p->i; }
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
new file mode 100644
@@ -0,0 +1,23 @@
+/* PR c/51628. */
+/* { dg-do compile } */
+/* { dg-options "-O" } */
+
+void foo (int *);
+
+int *
+bar (int n, int k, void *ptr)
+{
+ struct A
+ {
+ int c[k];
+ int x[n];
+ } __attribute__ ((packed, aligned (4)));
+ struct A *p = (struct A *) ptr;
+
+ int *p0, *p1;
+ p0 = p->x;
+ foo (p0);
+ p1 = &p->x[1];
+ foo (p1);
+ return &p->x[1];
+}
new file mode 100644
@@ -0,0 +1,26 @@
+/* PR c/51628. */
+/* { dg-do compile } */
+/* { dg-options "-O" } */
+
+void foo (int *);
+
+int *
+bar (int n, int k, void *ptr)
+{
+ struct A
+ {
+ char c[k];
+ int x[n];
+ } __attribute__ ((packed));
+ struct A *p = (struct A *) ptr;
+
+ int *p0, *p1;
+ p0 = p->x;
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
+ foo (p0);
+ p1 = &p->x[1];
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
+ foo (p1);
+ return &p->x[1];
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
+}
new file mode 100644
@@ -0,0 +1,11 @@
+/* PR c/51628. */
+/* { dg-do compile } */
+/* { dg-options "-O -Wno-incompatible-pointer-types" } */
+
+struct B { int i; };
+struct C { struct B b; } __attribute__ ((packed));
+
+extern struct C *p;
+
+long* g8 (void) { return p; }
+/* { dg-warning "increases the alignment of '.*' pointer from 1 to " "" { target *-*-* } .-1 } */
new file mode 100644
@@ -0,0 +1,11 @@
+/* PR c/51628. */
+/* { dg-do compile } */
+/* { dg-options "-O -Wno-incompatible-pointer-types" } */
+
+struct B { int i; };
+struct C { struct B b; } __attribute__ ((packed));
+
+extern struct C p[];
+
+long* g8 (void) { return p; }
+/* { dg-warning "increases the alignment of '.*' pointer from 1 to " "" { target *-*-* } .-1 } */
new file mode 100644
@@ -0,0 +1,9 @@
+/* PR c/51628. */
+/* { dg-do compile } */
+/* { dg-options "-O -Wno-incompatible-pointer-types" } */
+
+struct B { int i; };
+struct C { struct B b; } __attribute__ ((packed));
+
+int* g4 (struct C *p) { return &p->b; }
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
new file mode 100644
@@ -0,0 +1,9 @@
+/* PR c/51628. */
+/* { dg-do compile } */
+/* { dg-options "-O -Wno-incompatible-pointer-types" } */
+
+struct A {
+ int i;
+} __attribute__ ((packed));
+
+char* f0 (struct A *p) { return &p->i; }
new file mode 100644
@@ -0,0 +1,10 @@
+/* PR c/51628. */
+/* { dg-do compile } */
+/* { dg-options "-O -Wno-incompatible-pointer-types" } */
+
+struct A {
+ int i;
+} __attribute__ ((packed));
+
+short* f2 (struct A *p) { return &p->i; }
+/* { dg-warning "may result in an unaligned pointer value" "" { target *-*-* } .-1 } */
new file mode 100644
@@ -0,0 +1,9 @@
+/* PR c/51628. */
+/* { dg-do compile } */
+/* { dg-options "-O -Wno-incompatible-pointer-types" } */
+
+struct B { int i; };
+struct C { struct B b; } __attribute__ ((packed));
+
+long* g8 (struct C *p) { return p; }
+/* { dg-warning "increases the alignment of '.*' pointer from 1 to " "" { target *-*-* } .-1 } */
@@ -1,5 +1,5 @@
/* { dg-do run } */
-/* { dg-options "-O2 -mavx512bw" } */
+/* { dg-options "-O2 -mavx512bw -Wno-address-of-packed-member" } */
/* { dg-require-effective-target avx512bw } */
#define AVX512BW
@@ -1,5 +1,5 @@
/* { dg-do run } */
-/* { dg-options "-O2 -mavx512f" } */
+/* { dg-options "-O2 -mavx512f -Wno-address-of-packed-member" } */
/* { dg-require-effective-target avx512f } */
#define AVX512F
@@ -1,5 +1,5 @@
/* { dg-do run } */
-/* { dg-options "-O2 -mavx512f" } */
+/* { dg-options "-O2 -mavx512f -Wno-address-of-packed-member" } */
/* { dg-require-effective-target avx512f } */
#define AVX512F
@@ -1,5 +1,5 @@
/* { dg-do run } */
-/* { dg-options "-O2 -mavx512bw -mavx512vl" } */
+/* { dg-options "-O2 -mavx512bw -mavx512vl -Wno-address-of-packed-member" } */
/* { dg-require-effective-target avx512vl } */
/* { dg-require-effective-target avx512bw } */
@@ -1,5 +1,5 @@
/* { dg-do run } */
-/* { dg-options "-O2 -mavx512vl" } */
+/* { dg-options "-O2 -mavx512vl -Wno-address-of-packed-member" } */
/* { dg-require-effective-target avx512vl } */
#define AVX512VL
@@ -1,5 +1,5 @@
/* { dg-do run } */
-/* { dg-options "-O2 -mavx512vl" } */
+/* { dg-options "-O2 -mavx512vl -Wno-address-of-packed-member" } */
/* { dg-require-effective-target avx512vl } */
#define AVX512VL
@@ -177,6 +177,9 @@ read_sleb128 (const unsigned char *p, _sleb128_t *val)
The function returns P incremented past the value. BASE is as given
by base_of_encoded_value for this encoding in the appropriate context. */
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Waddress-of-packed-member"
+
static const unsigned char *
read_encoded_value_with_base (unsigned char encoding, _Unwind_Ptr base,
const unsigned char *p, _Unwind_Ptr *val)
@@ -270,6 +273,8 @@ read_encoded_value_with_base (unsigned char encoding, _Unwind_Ptr base,
return p;
}
+#pragma GCC diagnostic pop
+
#ifndef NO_BASE_OF_ENCODED_VALUE
/* Like read_encoded_value_with_base, but get the base from the context
--
2.17.1