Author: Alastair Houghton Date: 2024-06-10T10:21:13-04:00 New Revision: fe1301b5d846e96655ae6981789f677de6c7572d
URL: https://github.com/llvm/llvm-project/commit/fe1301b5d846e96655ae6981789f677de6c7572d DIFF: https://github.com/llvm/llvm-project/commit/fe1301b5d846e96655ae6981789f677de6c7572d.diff LOG: [libunwind] Tweak tests for musl support. (#85097) We can't use `dladdr()` in the tests, because when we're statically linking with musl that function is a no-op. Additionally, because musl disables emission of unwind information in its build, and because its signal trampolines don't include unwind information, tests that involve unwinding through a signal handler won't work and need to be disabled for musl. rdar://123436891 Added: Modified: libunwind/test/floatregister.pass.cpp libunwind/test/forceunwind.pass.cpp libunwind/test/signal_unwind.pass.cpp libunwind/test/unwind_leaffunction.pass.cpp Removed: ################################################################################ diff --git a/libunwind/test/floatregister.pass.cpp b/libunwind/test/floatregister.pass.cpp index 64107e6d490b7..ce4481bdf8287 100644 --- a/libunwind/test/floatregister.pass.cpp +++ b/libunwind/test/floatregister.pass.cpp @@ -11,20 +11,27 @@ // Basic test for float registers number are accepted. -#include <dlfcn.h> #include <stdlib.h> #include <string.h> #include <unwind.h> +// Using __attribute__((section("main_func"))) is ELF specific, but then +// this entire test is marked as requiring Linux, so we should be good. +// +// We don't use dladdr() because on musl it's a no-op when statically linked. +extern char __start_main_func; +extern char __stop_main_func; + _Unwind_Reason_Code frame_handler(struct _Unwind_Context *ctx, void *arg) { (void)arg; - Dl_info info = {0, 0, 0, 0}; - // Unwind util the main is reached, above frames depend on the platform and + // Unwind until the main is reached, above frames depend on the platform and // architecture. - if (dladdr(reinterpret_cast<void *>(_Unwind_GetIP(ctx)), &info) && - info.dli_sname && !strcmp("main", info.dli_sname)) + uintptr_t ip = _Unwind_GetIP(ctx); + if (ip >= (uintptr_t)&__start_main_func && + ip < (uintptr_t)&__stop_main_func) { _Exit(0); + } return _URC_NO_REASON; } @@ -45,7 +52,7 @@ __attribute__((noinline)) void foo() { _Unwind_Backtrace(frame_handler, NULL); } -int main() { +__attribute__((section("main_func"))) int main() { foo(); return -2; } diff --git a/libunwind/test/forceunwind.pass.cpp b/libunwind/test/forceunwind.pass.cpp index db499d8bc3089..344034e1ea5f5 100644 --- a/libunwind/test/forceunwind.pass.cpp +++ b/libunwind/test/forceunwind.pass.cpp @@ -17,7 +17,6 @@ #undef NDEBUG #include <assert.h> -#include <dlfcn.h> #include <signal.h> #include <stdint.h> #include <stdio.h> @@ -27,6 +26,13 @@ #include <unistd.h> #include <unwind.h> +// Using __attribute__((section("main_func"))) is Linux specific, but then +// this entire test is marked as requiring Linux, so we should be good. +// +// We don't use dladdr() because on musl it's a no-op when statically linked. +extern char __start_main_func; +extern char __stop_main_func; + void foo(); _Unwind_Exception ex; @@ -41,14 +47,14 @@ _Unwind_Reason_Code stop(int version, _Unwind_Action actions, assert(exceptionObject == &ex); assert(stop_parameter == &foo); - Dl_info info = {0, 0, 0, 0}; - - // Unwind util the main is reached, above frames depend on the platform and + // Unwind until the main is reached, above frames depend on the platform and // architecture. - if (dladdr(reinterpret_cast<void *>(_Unwind_GetIP(context)), &info) && - info.dli_sname && !strcmp("main", info.dli_sname)) { + uintptr_t ip = _Unwind_GetIP(context); + if (ip >= (uintptr_t)&__start_main_func && + ip < (uintptr_t)&__stop_main_func) { _Exit(0); } + return _URC_NO_REASON; } @@ -66,7 +72,7 @@ __attribute__((noinline)) void foo() { _Unwind_ForcedUnwind(e, stop, (void *)&foo); } -int main() { +__attribute__((section("main_func"))) int main() { foo(); return -2; } diff --git a/libunwind/test/signal_unwind.pass.cpp b/libunwind/test/signal_unwind.pass.cpp index 954a5d4ba3db1..1c1566415a4d4 100644 --- a/libunwind/test/signal_unwind.pass.cpp +++ b/libunwind/test/signal_unwind.pass.cpp @@ -13,9 +13,15 @@ // TODO: Figure out why this fails with Memory Sanitizer. // XFAIL: msan +// Note: this test fails on musl because: +// +// (a) musl disables emission of unwind information for its build, and +// (b) musl's signal trampolines don't include unwind information +// +// XFAIL: target={{.*}}-musl + #undef NDEBUG #include <assert.h> -#include <dlfcn.h> #include <signal.h> #include <stdio.h> #include <stdlib.h> @@ -24,16 +30,24 @@ #include <unistd.h> #include <unwind.h> +// Using __attribute__((section("main_func"))) is ELF specific, but then +// this entire test is marked as requiring Linux, so we should be good. +// +// We don't use dladdr() because on musl it's a no-op when statically linked. +extern char __start_main_func; +extern char __stop_main_func; + _Unwind_Reason_Code frame_handler(struct _Unwind_Context* ctx, void* arg) { (void)arg; - Dl_info info = { 0, 0, 0, 0 }; - // Unwind util the main is reached, above frames depend on the platform and + // Unwind until the main is reached, above frames depend on the platform and // architecture. - if (dladdr(reinterpret_cast<void *>(_Unwind_GetIP(ctx)), &info) && - info.dli_sname && !strcmp("main", info.dli_sname)) { + uintptr_t ip = _Unwind_GetIP(ctx); + if (ip >= (uintptr_t)&__start_main_func && + ip < (uintptr_t)&__stop_main_func) { _Exit(0); } + return _URC_NO_REASON; } @@ -43,7 +57,7 @@ void signal_handler(int signum) { _Exit(-1); } -int main(int, char**) { +__attribute__((section("main_func"))) int main(int, char **) { signal(SIGUSR1, signal_handler); kill(getpid(), SIGUSR1); return -2; diff --git a/libunwind/test/unwind_leaffunction.pass.cpp b/libunwind/test/unwind_leaffunction.pass.cpp index 112a5968247a4..98de7dc43260c 100644 --- a/libunwind/test/unwind_leaffunction.pass.cpp +++ b/libunwind/test/unwind_leaffunction.pass.cpp @@ -13,9 +13,15 @@ // TODO: Figure out why this fails with Memory Sanitizer. // XFAIL: msan +// Note: this test fails on musl because: +// +// (a) musl disables emission of unwind information for its build, and +// (b) musl's signal trampolines don't include unwind information +// +// XFAIL: target={{.*}}-musl + #undef NDEBUG #include <assert.h> -#include <dlfcn.h> #include <signal.h> #include <stdio.h> #include <stdlib.h> @@ -24,16 +30,24 @@ #include <unistd.h> #include <unwind.h> +// Using __attribute__((section("main_func"))) is ELF specific, but then +// this entire test is marked as requiring Linux, so we should be good. +// +// We don't use dladdr() because on musl it's a no-op when statically linked. +extern char __start_main_func; +extern char __stop_main_func; + _Unwind_Reason_Code frame_handler(struct _Unwind_Context* ctx, void* arg) { (void)arg; - Dl_info info = { 0, 0, 0, 0 }; // Unwind until the main is reached, above frames depend on the platform and // architecture. - if (dladdr(reinterpret_cast<void *>(_Unwind_GetIP(ctx)), &info) && - info.dli_sname && !strcmp("main", info.dli_sname)) { + uintptr_t ip = _Unwind_GetIP(ctx); + if (ip >= (uintptr_t)&__start_main_func && + ip < (uintptr_t)&__stop_main_func) { _Exit(0); } + return _URC_NO_REASON; } @@ -56,7 +70,7 @@ __attribute__((noinline)) void crashing_leaf_func(int do_trap) { __builtin_trap(); } -int main(int, char**) { +__attribute__((section("main_func"))) int main(int, char **) { signal(SIGTRAP, signal_handler); signal(SIGILL, signal_handler); crashing_leaf_func(1); _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
