diff --git a/CMakeLists.txt b/CMakeLists.txt
index fc90e4be2b0a3..78ff7da591f4c 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -229,11 +229,13 @@ ELSE()
        -Wold-style-cast \
        -Woverloaded-virtual \
        -Wpedantic \
-       -Wredundant-decls \
        -Wsuggest-override \
        -Wunused-macros \
        -Wzero-as-null-pointer-constant \
        -Wno-unknown-warning-option")
+    IF (NOT ${CMAKE_SYSTEM_NAME} MATCHES Windows)
+        SET(CATA_WARNINGS "${CATA_WARNINGS} -Wredundant-decls")
+    ENDIF()
     # Compact the whitespace in the warning string
     string(REGEX REPLACE "[\t ]+" " " CATA_WARNINGS "${CATA_WARNINGS}")
     SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${CATA_WARNINGS}")
diff --git a/src/posix_time.cpp b/src/posix_time.cpp
index bcee8631fc91a..39336a09cf405 100644
--- a/src/posix_time.cpp
+++ b/src/posix_time.cpp
@@ -1,6 +1,6 @@
 #include "posix_time.h"
 
-#if defined(_WIN32) && !defined(__CYGWIN__)
+#if defined(_WIN32) && !defined(__CYGWIN__) && !defined(WINPTHREAD_API)
 #include <cerrno>
 
 int
diff --git a/src/posix_time.h b/src/posix_time.h
index 5b822e67f070b..6e4a2ee808bf3 100644
--- a/src/posix_time.h
+++ b/src/posix_time.h
@@ -7,7 +7,7 @@
 
 #include <ctime> // IWYU pragma: keep
 
-#if defined(_WIN32) && !defined(__CYGWIN__)
+#if defined(_WIN32) && !defined(__CYGWIN__) && !defined(WINPTHREAD_API)
 /* Windows platforms.  */
 
 /* Windows lacks the nanosleep() function. The following code was stuffed