gcc/SOURCES/gcc11-libsanitizer-pthread.patch
2022-05-17 15:39:43 +00:00

55 lines
1.8 KiB
Diff

Backported from LLVM upstream:
commit ef14b78d9a144ba81ba02083fe21eb286a88732b
Author: Florian Weimer <fweimer@redhat.com>
Date: Tue Feb 8 12:46:41 2022 -0800
[sanitizer] Use _thread_db_sizeof_pthread to obtain struct pthread size
This symbol has been exported (as an internal GLIBC_PRIVATE symbol) from libc.so.6 starting with glibc 2.34. glibc uses it internally for its libthread_db implementation to enable thread debugging on GDB, so it is unlikely to go away for now.
Fixes #52989.
Reviewed By: #sanitizers, MaskRay, vitalybuka
Differential Revision: https://reviews.llvm.org/D119007
--- a/libsanitizer/sanitizer_common/sanitizer_linux_libcdep.cpp
+++ b/libsanitizer/sanitizer_common/sanitizer_linux_libcdep.cpp
@@ -265,10 +265,8 @@ void InitTlsSize() { }
// sizeof(struct pthread) from glibc.
static atomic_uintptr_t thread_descriptor_size;
-uptr ThreadDescriptorSize() {
- uptr val = atomic_load_relaxed(&thread_descriptor_size);
- if (val)
- return val;
+static uptr ThreadDescriptorSizeFallback() {
+ uptr val = 0;
#if defined(__x86_64__) || defined(__i386__) || defined(__arm__)
int major;
int minor;
@@ -323,8 +321,21 @@ uptr ThreadDescriptorSize() {
#elif defined(__s390__)
val = FIRST_32_SECOND_64(1152, 1776); // valid for glibc 2.22
#endif
+ return val;
+}
+
+uptr ThreadDescriptorSize() {
+ uptr val = atomic_load_relaxed(&thread_descriptor_size);
if (val)
- atomic_store_relaxed(&thread_descriptor_size, val);
+ return val;
+ // _thread_db_sizeof_pthread is a GLIBC_PRIVATE symbol that is exported in
+ // glibc 2.34 and later.
+ if (unsigned *psizeof = static_cast<unsigned *>(
+ dlsym(RTLD_DEFAULT, "_thread_db_sizeof_pthread")))
+ val = *psizeof;
+ if (!val)
+ val = ThreadDescriptorSizeFallback();
+ atomic_store_relaxed(&thread_descriptor_size, val);
return val;
}