[asan] Default to -fsanitize-address-use-odr-indicator for non-Windows
This enables odr indicators on all platforms and private aliases on non-Windows.
Note that GCC also uses private aliases: this fixes bogus
`The following global variable is not properly aligned.` errors for interposed global variables
Fix https://github.com/google/sanitizers/issues/398
Fix https://github.com/google/sanitizers/issues/1017
Fix https://github.com/llvm/llvm-project/issues/36893 (we can restore D46665)
Global variables of non-hasExactDefinition() linkages (i.e.
linkonce/linkonce_odr/weak/weak_odr/common/external_weak) are not instrumented.
If an instrumented variable gets interposed to an uninstrumented variable due to
symbol interposition (e.g. in issue 36893, _ZTS1A in foo.so is resolved to _ZTS1A in
the executable), there may be a bogus error.
With private aliases, the register code will not resolve to a definition in
another module, and thus prevent the issue.
Cons: minor size increase. This is mainly due to extra `__odr_asan_gen_*` symbols.
(ELF) In addition, in relocatable files private aliases replace some relocations
referencing global symbols with .L symbols and may introduce some STT_SECTION symbols.
For lld, with -g0, the size increase is 0.07~0.09% for many configurations I
have tested: -O0, -O1, -O2, -O3, -O2 -ffunction-sections -fdata-sections
-Wl,--gc-sections. With -g1 or above, the size increase ratio will be even smaller.
This patch obsoletes D92078.
Don't migrate Windows for now: the static data member of a specialization
`std::num_put<char>::id` is a weak symbol, as well as its ODR indicator.
Unfortunately, link.exe (and lld without -lldmingw) generally doesn't support
duplicate weak definitions (weak symbols in different TUs likely pick different
defined external symbols and conflict).
Differential Revision: https://reviews.llvm.org/D137227
GitOrigin-RevId: 1ada819c237bf724e6eaa1c82b2742e3eb57a5d5
diff --git a/test/asan/TestCases/Linux/odr-violation.cpp b/test/asan/TestCases/Linux/odr-violation.cpp
index 1c8ea99..a86e032 100644
--- a/test/asan/TestCases/Linux/odr-violation.cpp
+++ b/test/asan/TestCases/Linux/odr-violation.cpp
@@ -6,16 +6,19 @@
// We use fast_unwind_on_malloc=0 to have full unwinding even w/o frame
// pointers. This setting is not on by default because it's too expensive.
//
+// Note, -asan-use-private-alias=1 -asan-use-odr-indicator=1 is the default.
+// -fno-sanitize-address-use-odr-indicator turns off both.
+//
// Different size: detect a bug if detect_odr_violation>=1
-// RUN: %clangxx_asan -g -DBUILD_SO=1 -fPIC -shared %s -o %dynamiclib
-// RUN: %clangxx_asan -g %s %ld_flags_rpath_exe -o %t-ODR-EXE
+// RUN: %clangxx_asan -g -DBUILD_SO=1 -fPIC -shared -fno-sanitize-address-use-odr-indicator %s -o %dynamiclib
+// RUN: %clangxx_asan -g -fno-sanitize-address-use-odr-indicator %s %ld_flags_rpath_exe -o %t-ODR-EXE
// RUN: %env_asan_opts=fast_unwind_on_malloc=0:detect_odr_violation=1 not %run %t-ODR-EXE 2>&1 | FileCheck %s
// RUN: %env_asan_opts=fast_unwind_on_malloc=0:detect_odr_violation=2 not %run %t-ODR-EXE 2>&1 | FileCheck %s
// RUN: %env_asan_opts=fast_unwind_on_malloc=0:detect_odr_violation=0 %run %t-ODR-EXE 2>&1 | FileCheck %s --check-prefix=DISABLED
// RUN: %env_asan_opts=fast_unwind_on_malloc=0 not %run %t-ODR-EXE 2>&1 | FileCheck %s
//
// Same size: report a bug only if detect_odr_violation>=2.
-// RUN: %clangxx_asan -g -DBUILD_SO=1 -fPIC -shared %s -o %dynamiclib -DSZ=100
+// RUN: %clangxx_asan -g -DBUILD_SO=1 -fPIC -shared -fno-sanitize-address-use-odr-indicator %s -o %dynamiclib -DSZ=100
// RUN: %env_asan_opts=fast_unwind_on_malloc=0:detect_odr_violation=1 %run %t-ODR-EXE 2>&1 | FileCheck %s --check-prefix=DISABLED
// RUN: %env_asan_opts=fast_unwind_on_malloc=0:detect_odr_violation=2 not %run %t-ODR-EXE 2>&1 | FileCheck %s
// RUN: %env_asan_opts=fast_unwind_on_malloc=0 not %run %t-ODR-EXE 2>&1 | FileCheck %s
@@ -26,13 +29,13 @@
// RUN: rm -f %t.supp
//
// Use private aliases for global variables without indicator symbol.
-// RUN: %clangxx_asan -g -DBUILD_SO=1 -fPIC -shared -mllvm -asan-use-private-alias %s -o %dynamiclib -DSZ=100
-// RUN: %clangxx_asan -g -mllvm -asan-use-private-alias %s %ld_flags_rpath_exe -o %t-ODR-EXE
+// RUN: %clangxx_asan -g -DBUILD_SO=1 -fPIC -shared -mllvm -asan-use-odr-indicator=0 %s -o %dynamiclib -DSZ=100
+// RUN: %clangxx_asan -g -mllvm -asan-use-odr-indicator=0 %s %ld_flags_rpath_exe -o %t-ODR-EXE
// RUN: %env_asan_opts=fast_unwind_on_malloc=0 %run %t-ODR-EXE 2>&1 | FileCheck %s --check-prefix=DISABLED
// Use private aliases for global variables: use indicator symbol to detect ODR violation.
-// RUN: %clangxx_asan -g -DBUILD_SO=1 -fPIC -shared -mllvm -asan-use-private-alias -mllvm -asan-use-odr-indicator %s -o %dynamiclib -DSZ=100
-// RUN: %clangxx_asan -g -mllvm -asan-use-private-alias -mllvm -asan-use-odr-indicator %s %ld_flags_rpath_exe -o %t-ODR-EXE
+// RUN: %clangxx_asan -g -DBUILD_SO=1 -fPIC -shared %s -o %dynamiclib -DSZ=100
+// RUN: %clangxx_asan -g %s %ld_flags_rpath_exe -o %t-ODR-EXE
// RUN: %env_asan_opts=fast_unwind_on_malloc=0 not %run %t-ODR-EXE 2>&1 | FileCheck %s
// Same as above but with clang switches.
diff --git a/test/asan/TestCases/Linux/odr_indicators.cpp b/test/asan/TestCases/Linux/odr_indicators.cpp
index 36176b5..583f6e6 100644
--- a/test/asan/TestCases/Linux/odr_indicators.cpp
+++ b/test/asan/TestCases/Linux/odr_indicators.cpp
@@ -1,4 +1,4 @@
-// RUN: %clangxx_asan -fPIC %s -o %t
+// RUN: %clangxx_asan -fno-sanitize-address-use-odr-indicator -fPIC %s -o %t
// RUN: %env_asan_opts=report_globals=2 %run %t 2>&1 | FileCheck %s --check-prefixes=CHECK,INDICATOR0
// RUN: %clangxx_asan -fsanitize-address-use-odr-indicator -fPIC %s -o %t
