Here we crash on a null fndecl ultimately because we haven't defined
the built-ins described in sanitizer.def. So
builtin_decl_explicit (BUILT_IN_ASAN_POINTER_SUBTRACT);
returns NULL_TREE, causing an ICE later.
DEF_SANITIZER_BUILTIN only actually defines the built-ins when flag_sanitize
has SANITIZE_ADDRESS, or some of the other SANITIZE_*, but it doesn't check
SANITIZE_KERNEL_ADDRESS or SANITIZE_USER_ADDRESS. Unfortunately, with
-fsanitize=address -fno-sanitize=kernel-address
or
-fsanitize=kernel-address -fno-sanitize=address
SANITIZE_ADDRESS ends up being unset from flag_sanitize even though
_USER/_KERNEL are set. That's because -fsanitize=address means
SANITIZE_ADDRESS | SANITIZE_USER_ADDRESS and -fsanitize=kernel-address
is SANITIZE_ADDRESS | SANITIZE_KERNEL_ADDRESS but parse_sanitizer_options
does
flags &= ~sanitizer_opts[i].flag;
so the subsequent -fno- unsets SANITIZE_ADDRESS. Then no sanitizer
built-ins are actually defined.
I'm not sure why SANITIZE_ADDRESS isn't just SANITIZE_USER_ADDRESS |
SANITIZE_KERNEL_ADDRESS, I don't think we need 3 bits.
Bootstrapped/regtested on x86_64-pc-linux-gnu, ok for trunk/12/11?
PR middle-end/108543
gcc/ChangeLog:
* opts.cc (parse_sanitizer_options): Don't clear SANITIZE_ADDRESS if it
was previously set.
gcc/testsuite/ChangeLog:
* c-c++-common/asan/pointer-subtract-5.c: New test.
* c-c++-common/asan/pointer-subtract-6.c: New test.
* c-c++-common/asan/pointer-subtract-7.c: New test.
* c-c++-common/asan/pointer-subtract-8.c: New test.
---
gcc/opts.cc | 5 ++++-
.../c-c++-common/asan/pointer-subtract-5.c | 15 +++++++++++++++
.../c-c++-common/asan/pointer-subtract-6.c | 15 +++++++++++++++
.../c-c++-common/asan/pointer-subtract-7.c | 15 +++++++++++++++
.../c-c++-common/asan/pointer-subtract-8.c | 15 +++++++++++++++
5 files changed, 64 insertions(+), 1 deletion(-)
create mode 100644 gcc/testsuite/c-c++-common/asan/pointer-subtract-5.c
create mode 100644 gcc/testsuite/c-c++-common/asan/pointer-subtract-6.c
create mode 100644 gcc/testsuite/c-c++-common/asan/pointer-subtract-7.c
create mode 100644 gcc/testsuite/c-c++-common/asan/pointer-subtract-8.c
diff --git a/gcc/opts.cc b/gcc/opts.cc
index 9ba47d7deaa..c042b03bd9f 100644
--- a/gcc/opts.cc
+++ b/gcc/opts.cc
@@ -2246,7 +2246,10 @@ parse_sanitizer_options (const char *p, location_t loc,
int scode,
flags |= sanitizer_opts[i].flag;
}
else
- flags &= ~sanitizer_opts[i].flag;
+ /* Don't clear SANITIZE_ADDRESS if it was previously set;
+ -fsanitize=address -fno-sanitize=kernel-address should
+ leave SANITIZE_ADDRESS set. */
+ flags &= (~sanitizer_opts[i].flag | SANITIZE_ADDRESS);
found = true;
break;
}
diff --git a/gcc/testsuite/c-c++-common/asan/pointer-subtract-5.c
b/gcc/testsuite/c-c++-common/asan/pointer-subtract-5.c
new file mode 100644
index 00000000000..867eda0e61e
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/asan/pointer-subtract-5.c
@@ -0,0 +1,15 @@
+/* PR middle-end/108543 */
+/* { dg-do compile } */
+/* { dg-options "-fsanitize=address -fno-sanitize=kernel-address
-fsanitize=pointer-subtract" } */
+
+struct S {
+ long _M_p;
+};
+
+typedef struct S S;
+
+__PTRDIFF_TYPE__
+f (S __x, S __y)
+{
+ return &__x._M_p - &__y._M_p;
+}
diff --git a/gcc/testsuite/c-c++-common/asan/pointer-subtract-6.c
b/gcc/testsuite/c-c++-common/asan/pointer-subtract-6.c
new file mode 100644
index 00000000000..785b90b3d98
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/asan/pointer-subtract-6.c
@@ -0,0 +1,15 @@
+/* PR middle-end/108543 */
+/* { dg-do compile } */
+/* { dg-options "-fsanitize=kernel-address -fno-sanitize=address
-fsanitize=pointer-subtract" } */
+
+struct S {
+ long _M_p;
+};
+
+typedef struct S S;
+
+__PTRDIFF_TYPE__
+f (S __x, S __y)
+{
+ return &__x._M_p - &__y._M_p;
+}
diff --git a/gcc/testsuite/c-c++-common/asan/pointer-subtract-7.c
b/gcc/testsuite/c-c++-common/asan/pointer-subtract-7.c
new file mode 100644
index 00000000000..11b63401b8c
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/asan/pointer-subtract-7.c
@@ -0,0 +1,15 @@
+/* PR middle-end/108543 */
+/* { dg-do compile } */
+/* { dg-options "-fno-sanitize=kernel-address -fsanitize=address
-fsanitize=pointer-subtract" } */
+
+struct S {
+ long _M_p;
+};
+
+typedef struct S S;
+
+__PTRDIFF_TYPE__
+f (S __x, S __y)
+{
+ return &__x._M_p - &__y._M_p;
+}
diff --git a/gcc/testsuite/c-c++-common/asan/pointer-subtract-8.c
b/gcc/testsuite/c-c++-common/asan/pointer-subtract-8.c
new file mode 100644
index 00000000000..ac2b9c3c1d9
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/asan/pointer-subtract-8.c
@@ -0,0 +1,15 @@
+/* PR middle-end/108543 */
+/* { dg-do compile } */
+/* { dg-options "-fno-sanitize=address -fsanitize=kernel-address
-fsanitize=pointer-subtract" } */
+
+struct S {
+ long _M_p;
+};
+
+typedef struct S S;
+
+__PTRDIFF_TYPE__
+f (S __x, S __y)
+{
+ return &__x._M_p - &__y._M_p;
+}
base-commit: 9fb9da3d38513d320bfea72050f7a59688595e0b
--
2.39.1
