diff --git a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.gen/lexically_normal.pass.cpp b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.gen/lexically_normal.pass.cpp
--- a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.gen/lexically_normal.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.gen/lexically_normal.pass.cpp
@@ -127,7 +127,7 @@
     const fs::path output = p.lexically_normal();
     if (!PathEq(output, TC.expect)) {
       Failed = true;
-      std::printf("TEST CASE #%d FAILED:\n"
+      std::fprintf(stderr, "TEST CASE #%d FAILED:\n"
                   "  Input: '%s'\n"
                   "  Expected: '%s'\n"
                   "  Output: '%s'\n",
diff --git a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.gen/lexically_relative_and_proximate.pass.cpp b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.gen/lexically_relative_and_proximate.pass.cpp
--- a/libcxx/test/std/input.output/filesystems/class.path/path.member/path.gen/lexically_relative_and_proximate.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/class.path/path.member/path.gen/lexically_relative_and_proximate.pass.cpp
@@ -62,7 +62,7 @@
     auto ReportErr = [&](const char* Testing, fs::path const& Output,
                                               fs::path const& Expected) {
       Failed = true;
-      std::printf("TEST CASE #%d FAILED:\n"
+      std::fprintf(stderr, "TEST CASE #%d FAILED:\n"
                   "  Testing: %s\n"
                   "  Input: '%s'\n"
                   "  Base: '%s'\n"
diff --git a/libcxx/test/std/input.output/filesystems/fs.op.funcs/fs.op.proximate/proximate.pass.cpp b/libcxx/test/std/input.output/filesystems/fs.op.funcs/fs.op.proximate/proximate.pass.cpp
--- a/libcxx/test/std/input.output/filesystems/fs.op.funcs/fs.op.proximate/proximate.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/fs.op.funcs/fs.op.proximate/proximate.pass.cpp
@@ -100,7 +100,7 @@
     const fs::path output = fs::proximate(p, TC.base, ec);
     if (ec) {
       TEST_CHECK(!ec);
-      std::printf("TEST CASE #%d FAILED:\n"
+      std::fprintf(stderr, "TEST CASE #%d FAILED:\n"
                   "  Input: '%s'\n"
                   "  Base: '%s'\n"
                   "  Expected: '%s'\n",
@@ -111,7 +111,7 @@
       const path canon_input = fs::weakly_canonical(TC.input);
       const path canon_base = fs::weakly_canonical(TC.base);
       const path lexically_p = canon_input.lexically_proximate(canon_base);
-      std::printf("TEST CASE #%d FAILED:\n"
+      std::fprintf(stderr, "TEST CASE #%d FAILED:\n"
                   "  Input: '%s'\n"
                   "  Base: '%s'\n"
                   "  Expected: '%s'\n"
diff --git a/libcxx/test/std/input.output/filesystems/fs.op.funcs/fs.op.weakly_canonical/weakly_canonical.pass.cpp b/libcxx/test/std/input.output/filesystems/fs.op.funcs/fs.op.weakly_canonical/weakly_canonical.pass.cpp
--- a/libcxx/test/std/input.output/filesystems/fs.op.funcs/fs.op.weakly_canonical/weakly_canonical.pass.cpp
+++ b/libcxx/test/std/input.output/filesystems/fs.op.funcs/fs.op.weakly_canonical/weakly_canonical.pass.cpp
@@ -65,7 +65,7 @@
     const fs::path output = fs::weakly_canonical(p);
     if (!PathEq(output, TC.expect)) {
       Failed = true;
-      std::printf("TEST CASE #%d FAILED:\n"
+      std::fprintf(stderr, "TEST CASE #%d FAILED:\n"
                   "  Input: '%s'\n"
                   "  Expected: '%s'\n"
                   "  Output: '%s'\n",