diff --git a/CMakeLists.txt b/CMakeLists.txt
index 684029524..b11215d26 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -245,7 +245,7 @@ if(MBEDTLS_FATAL_WARNINGS)
     endif(CMAKE_COMPILER_IS_CLANG OR CMAKE_COMPILER_IS_GNU)
 
     if (CMAKE_COMPILER_IS_IAR)
-        set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} --warning_are_errors")
+        set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} --warnings_are_errors")
     endif(CMAKE_COMPILER_IS_IAR)
 endif(MBEDTLS_FATAL_WARNINGS)
 
diff --git a/ChangeLog.d/bugfix_iar_typo.txt b/ChangeLog.d/bugfix_iar_typo.txt
new file mode 100644
index 000000000..95f97b1cb
--- /dev/null
+++ b/ChangeLog.d/bugfix_iar_typo.txt
@@ -0,0 +1,3 @@
+Bugfix
+   * Fixed an issue that caused compile errors when using CMake and the IAR
+     toolchain.