4 files changed, 19 insertions, 2 deletions
diff --git a/libc/test/UnitTest/CMakeLists.txt b/libc/test/UnitTest/CMakeLists.txt
index d92ab6f..f1a83fc 100644
--- a/libc/test/UnitTest/CMakeLists.txt
+++ b/libc/test/UnitTest/CMakeLists.txt
@@ -125,6 +125,7 @@ add_unittest_framework_library(
     RoundingModeUtils.h
   DEPENDS
     LibcTest
+    libc.test.UnitTest.ErrnoCheckingTest
     libc.test.UnitTest.string_utils
     libc.src.__support.CPP.array
     libc.src.__support.FPUtil.fp_bits
diff --git a/libc/test/UnitTest/FEnvSafeTest.cpp b/libc/test/UnitTest/FEnvSafeTest.cpp
index 168b1d4..f644569 100644
--- a/libc/test/UnitTest/FEnvSafeTest.cpp
+++ b/libc/test/UnitTest/FEnvSafeTest.cpp
@@ -9,8 +9,10 @@
 #include "FEnvSafeTest.h"
 
 #include "src/__support/FPUtil/FEnvImpl.h"
+#include "src/__support/libc_errno.h"
 #include "src/__support/macros/config.h"
 #include "src/__support/macros/properties/architectures.h"
+#include "test/UnitTest/ErrnoCheckingTest.h"
 
 namespace LIBC_NAMESPACE_DECL {
 namespace testing {
@@ -25,6 +27,10 @@ void FEnvSafeTest::TearDown() {
   if (!should_be_unchanged) {
     restore_fenv();
   }
+  // TODO (PR 135320): Remove this override once all FEnvSafeTest instances are
+  // updated to validate or ignore errno.
+  libc_errno = 0;
+  ErrnoCheckingTest::TearDown();
 }
 
 void FEnvSafeTest::get_fenv(fenv_t &fenv) {
diff --git a/libc/test/UnitTest/FEnvSafeTest.h b/libc/test/UnitTest/FEnvSafeTest.h
index a3c5e62..1e10629 100644
--- a/libc/test/UnitTest/FEnvSafeTest.h
+++ b/libc/test/UnitTest/FEnvSafeTest.h
@@ -12,6 +12,7 @@
 #include "hdr/types/fenv_t.h"
 #include "src/__support/CPP/utility.h"
 #include "src/__support/macros/config.h"
+#include "test/UnitTest/ErrnoCheckingTest.h"
 #include "test/UnitTest/Test.h"
 
 namespace LIBC_NAMESPACE_DECL {
@@ -20,7 +21,7 @@ namespace testing {
 // This provides a test fixture (or base class for other test fixtures) that
 // asserts that each test does not leave the FPU state represented by `fenv_t`
 // (aka `FPState`) perturbed from its initial state.
-class FEnvSafeTest : public Test {
+class FEnvSafeTest : public ErrnoCheckingTest {
 public:
   void TearDown() override;
 
diff --git a/libc/test/UnitTest/FPMatcher.h b/libc/test/UnitTest/FPMatcher.h
index da15cf2..592cd1b 100644
--- a/libc/test/UnitTest/FPMatcher.h
+++ b/libc/test/UnitTest/FPMatcher.h
@@ -14,8 +14,10 @@
 #include "src/__support/FPUtil/FEnvImpl.h"
 #include "src/__support/FPUtil/FPBits.h"
 #include "src/__support/FPUtil/fpbits_str.h"
+#include "src/__support/libc_errno.h"
 #include "src/__support/macros/config.h"
 #include "src/__support/macros/properties/architectures.h"
+#include "test/UnitTest/ErrnoCheckingTest.h"
 #include "test/UnitTest/RoundingModeUtils.h"
 #include "test/UnitTest/StringUtils.h"
 #include "test/UnitTest/Test.h"
@@ -166,7 +168,7 @@ CFPMatcher<T, C> getMatcherComplex(T expectedValue) {
   return CFPMatcher<T, C>(expectedValue);
 }
 
-template <typename T> struct FPTest : public Test {
+template <typename T> struct FPTest : public ErrnoCheckingTest {
   using FPBits = LIBC_NAMESPACE::fputil::FPBits<T>;
   using StorageType = typename FPBits::StorageType;
   static constexpr StorageType STORAGE_MAX =
@@ -191,6 +193,13 @@ template <typename T> struct FPTest : public Test {
       fputil::testing::RoundingMode::Downward,
       fputil::testing::RoundingMode::TowardZero,
   };
+
+  void TearDown() override {
+    // TODO (PR 135320): Remove this override once all FPTest instances are
+    // updated to validate or ignore errno.
+    libc_errno = 0;
+    ErrnoCheckingTest::TearDown();
+  }
 };
 
 // Add facility to test Flush-Denormal-To-Zero (FTZ) and Denormal-As-Zero (DAZ)