diff --git a/include/compat/bionic_host_libc_runtime.h b/include/compat/bionic_host_libc_runtime.h
index 5c8d44c..15c14d9 100644
--- a/include/compat/bionic_host_libc_runtime.h
+++ b/include/compat/bionic_host_libc_runtime.h
@@ -14,16 +14,16 @@ namespace mocktail::compat {
 // Android uses size_t fields here; glibc uses int and musl has no equivalent.
 // An all-zero fallback means unknown, not zero usage.
 struct BionicMallinfoSnapshot {
-  size_t arena = 0;
-  size_t ordblks = 0;
-  size_t smblks = 0;
-  size_t hblks = 0;
-  size_t hblkhd = 0;
-  size_t usmblks = 0;
-  size_t fsmblks = 0;
-  size_t uordblks = 0;
-  size_t fordblks = 0;
-  size_t keepcost = 0;
+  size_t arena;
+  size_t ordblks;
+  size_t smblks;
+  size_t hblks;
+  size_t hblkhd;
+  size_t usmblks;
+  size_t fsmblks;
+  size_t uordblks;
+  size_t fordblks;
+  size_t keepcost;
 };
 
 struct BionicLocaleState;
diff --git a/src/compat/bionic_host_libc_runtime.cc b/src/compat/bionic_host_libc_runtime.cc
index 9ec8eff..324e2e9 100644
--- a/src/compat/bionic_host_libc_runtime.cc
+++ b/src/compat/bionic_host_libc_runtime.cc
@@ -323,8 +323,13 @@ int BionicStrError(int error_number, char* buffer,
       ::strerror_r(error_number, host_buffer.data(), host_buffer.size());
   const char* message = HostStrErrorResult(host_result, host_buffer.data());
 
-  std::array<char, 64> unknown_buffer{};
-  if (message == nullptr) {
+  std::array<char, 256> unknown_buffer{};
+  const char* unknown_message = HostStrErrorResult(
+      ::strerror_r(-1, unknown_buffer.data(), unknown_buffer.size()),
+      unknown_buffer.data());
+  if (message == nullptr ||
+      (error_number != 0 && unknown_message != nullptr &&
+       std::strcmp(message, unknown_message) == 0)) {
     std::snprintf(unknown_buffer.data(), unknown_buffer.size(),
                   "Unknown error %d", error_number);
     message = unknown_buffer.data();
diff --git a/src/compat/bionic_pthread_create_runtime.cc b/src/compat/bionic_pthread_create_runtime.cc
index e34fcf6..af5ff8e 100644
--- a/src/compat/bionic_pthread_create_runtime.cc
+++ b/src/compat/bionic_pthread_create_runtime.cc
@@ -114,7 +114,7 @@ int CopySupportedThreadAttributes(const MocktailBionicPthreadAttr& source,
   if (RejectRealtimeScheduling(source.sched_policy)) {
     return EPERM;
   }
-  if (source.sched_policy != SCHED_NORMAL) {
+  if (source.sched_policy != SCHED_OTHER) {
     result = pthread_attr_setschedpolicy(destination, source.sched_policy);
     if (result != 0) {
       return result;
diff --git a/src/runtime/external_launch_broker.cc b/src/runtime/external_launch_broker.cc
index 3ea4632..b723e28 100644
--- a/src/runtime/external_launch_broker.cc
+++ b/src/runtime/external_launch_broker.cc
@@ -10,6 +10,7 @@
 #include <sys/eventfd.h>
 #include <sys/socket.h>
 #include <sys/stat.h>
+#include <sys/time.h>
 #include <sys/un.h>
 #include <unistd.h>
 
diff --git a/tests/bionic_host_libc_runtime_test.cc b/tests/bionic_host_libc_runtime_test.cc
index 663bea7..b67e753 100644
--- a/tests/bionic_host_libc_runtime_test.cc
+++ b/tests/bionic_host_libc_runtime_test.cc
@@ -13,6 +13,7 @@
 #include <cstdint>
 #include <cstring>
 #include <limits>
+#include <string>
 #include <thread>
 
 #include "libc_shim/libc_shim.h"
@@ -214,9 +215,18 @@ TEST(BionicHostLibcRuntimeTest, UsesBionicPosixStrErrorContract) {
   EXPECT_NE(std::strstr(buffer.data(), "Invalid"), nullptr);
   EXPECT_EQ(errno, EDOM);
 
-  buffer.fill('\0');
-  EXPECT_EQ(mocktail_bionic_strerror_r(4567, buffer.data(), buffer.size()), 0);
-  EXPECT_NE(std::strstr(buffer.data(), "4567"), nullptr);
+  EXPECT_EQ(mocktail_bionic_strerror_r(0, buffer.data(), buffer.size()), 0);
+  EXPECT_STREQ(buffer.data(), std::strerror(0));
+  EXPECT_EQ(errno, EDOM);
+
+  for (const int error_number : {-1, 4567, INT_MIN, INT_MAX}) {
+    errno = EDOM;
+    ASSERT_EQ(mocktail_bionic_strerror_r(error_number, buffer.data(),
+                                       buffer.size()), 0);
+    EXPECT_EQ(std::string(buffer.data()),
+              "Unknown error " + std::to_string(error_number));
+    EXPECT_EQ(errno, EDOM);
+  }
 
   std::array<char, 2> truncated{};
   errno = 0;
diff --git a/third_party/mcpelauncher-linker/include/assert.h b/third_party/mcpelauncher-linker/include/assert.h
index 7205cce..3ffb4a1 100644
--- a/third_party/mcpelauncher-linker/include/assert.h
+++ b/third_party/mcpelauncher-linker/include/assert.h
@@ -1,4 +1,5 @@
+#include <sys/cdefs.h>
 #include "../bionic/libc/include/assert.h"
 #ifdef __BIONIC__
 #undef __BIONIC__
-#endif
\ No newline at end of file
+#endif
diff --git a/third_party/mcpelauncher-linker/include/compat.h b/third_party/mcpelauncher-linker/include/compat.h
index 4f435e0..4ce7490 100644
--- a/third_party/mcpelauncher-linker/include/compat.h
+++ b/third_party/mcpelauncher-linker/include/compat.h
@@ -15,8 +15,12 @@
 typedef std::atomic_int atomic_int;
 typedef std::atomic_uint atomic_uint;
 #endif
+#ifndef PAGE_SIZE
 #define PAGE_SIZE 4096
+#endif
+#ifndef PAGE_MASK
 #define PAGE_MASK (~(PAGE_SIZE - 1))
+#endif
 #if !defined(__APPLE__) && !defined(__FreeBSD__)
 #define DEF_WEAK(a)
 #define __BIONIC_ALIGN(__value, __alignment) (((__value) + (__alignment)-1) & ~((__alignment)-1))
diff --git a/third_party/mcpelauncher-linker/include/sys/cdefs.h b/third_party/mcpelauncher-linker/include/sys/cdefs.h
index 3e6455b..53749da 100644
--- a/third_party/mcpelauncher-linker/include/sys/cdefs.h
+++ b/third_party/mcpelauncher-linker/include/sys/cdefs.h
@@ -1,6 +1,12 @@
 #pragma once
 #ifndef __APPLE__
+#pragma push_macro("_FORTIFY_SOURCE")
+#pragma push_macro("__bos")
+#undef _FORTIFY_SOURCE
+#undef __bos
 #include "../../bionic/libc/include/sys/cdefs.h"
+#pragma pop_macro("__bos")
+#pragma pop_macro("_FORTIFY_SOURCE")
 #endif
 #if defined(__has_include_next)
 #if __has_include_next(<sys/cdefs.h>)