[libc-commits] [libc] [libc] Make getauxval test hermetic (PR #210706)

[Pavel Labath via libc-commits]

https://github.com/labath updated https://github.com/llvm/llvm-project/pull/210706

>From ccf86f5eb50bc2894b00e7f5ab698712e5be1fdd Mon Sep 17 00:00:00 2001
From: Pavel Labath <pavel at labath.sk>
Date: Mon, 20 Jul 2026 12:49:57 +0000
Subject: [PATCH] [libc] Make getauxval test hermetic

---
 libc/cmake/modules/LLVMLibCTestRules.cmake  | 12 +++---------
 libc/test/UnitTest/HermeticTestUtils.cpp    |  8 --------
 libc/test/src/sys/auxv/linux/CMakeLists.txt |  2 +-
 3 files changed, 4 insertions(+), 18 deletions(-)

diff --git a/libc/cmake/modules/LLVMLibCTestRules.cmake b/libc/cmake/modules/LLVMLibCTestRules.cmake
index fdc7764c65177..332ec1084413e 100644
--- a/libc/cmake/modules/LLVMLibCTestRules.cmake
+++ b/libc/cmake/modules/LLVMLibCTestRules.cmake
@@ -793,6 +793,9 @@ function(add_libc_hermetic test_name)
       libc.src.unistd.fork
       libc.src.unistd.pipe
   )
+  if (LIBC_TARGET_ARCHITECTURE_IS_AARCH64 AND NOT(LIBC_TARGET_OS_IS_BAREMETAL))
+    list(APPEND fq_deps_list libc.src.sys.auxv.getauxval)
+  endif()
 
   if(libc.src.compiler.__stack_chk_fail IN_LIST TARGET_LLVMLIBC_ENTRYPOINTS)
     # __stack_chk_fail should always be included if supported to allow building
@@ -920,15 +923,6 @@ function(add_libc_hermetic test_name)
                    LibcTest.hermetic
                    libc.test.UnitTest.ErrnoSetterMatcher
                    ${fq_deps_list})
-  # TODO: currently the dependency chain is broken such that getauxval cannot properly
-  # propagate to hermetic tests. This is a temporary workaround.
-  if (LIBC_TARGET_ARCHITECTURE_IS_AARCH64 AND NOT(LIBC_TARGET_OS_IS_BAREMETAL))
-    target_link_libraries(
-      ${fq_build_target_name}
-      PRIVATE
-        libc.src.sys.auxv.getauxval
-    )
-  endif()
 
   if(NOT HERMETIC_TEST_NO_RUN_POSTBUILD)
     if (LIBC_TEST_CMD)
diff --git a/libc/test/UnitTest/HermeticTestUtils.cpp b/libc/test/UnitTest/HermeticTestUtils.cpp
index 5ce661b2202c0..f7fc52e87ecc8 100644
--- a/libc/test/UnitTest/HermeticTestUtils.cpp
+++ b/libc/test/UnitTest/HermeticTestUtils.cpp
@@ -25,14 +25,6 @@ void *memmove(void *dst, const void *src, size_t count);
 void *memset(void *ptr, int value, size_t count);
 int atexit(void (*func)(void));
 
-// TODO: It seems that some old test frameworks does not use
-// add_libc_hermetic_test properly. Such that they won't get correct linkage
-// against the object containing this function. We create a dummy function that
-// always returns 0 to indicate a failure.
-[[gnu::weak]] unsigned long getauxval([[maybe_unused]] unsigned long id) {
-  return 0;
-}
-
 } // namespace LIBC_NAMESPACE_DECL
 
 constexpr uint64_t ALIGNMENT = alignof(uintptr_t);
diff --git a/libc/test/src/sys/auxv/linux/CMakeLists.txt b/libc/test/src/sys/auxv/linux/CMakeLists.txt
index e4c3b782cd326..92617049401a2 100644
--- a/libc/test/src/sys/auxv/linux/CMakeLists.txt
+++ b/libc/test/src/sys/auxv/linux/CMakeLists.txt
@@ -1,5 +1,5 @@
 add_custom_target(libc_sys_auxv_unittests)
-add_libc_unittest(
+add_libc_test(
   getauxval_test
   SUITE
     libc_sys_auxv_unittests