diff --git a/CMakeLists.txt b/CMakeLists.txt
index b8cd44c..70926e8 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -62,7 +62,7 @@ if(WIN32)
     check_function_exists(_fstat64 GMIO_HAVE_WIN__FSTAT64_FUNC)
 endif()
 
-# Find available C99 and compiler/OS specific features
+# Check available C99 and compiler/OS specific features
 if(NOT BUILD_STRICT_C90)
     check_function_exists(strtof GMIO_HAVE_STRTOF_FUNC)
     check_function_exists(powf GMIO_HAVE_POWF_FUNC)
@@ -79,7 +79,7 @@ if(NOT BUILD_STRICT_C90)
         check_c_source_compiles(
             "#include <malloc.h>
              int main() { void* ptr = _alloca(256); return 0; }"
-            GMIO_HAVE_WIN_ALLOCA_FUNC) # TODO: rename to GMIO_HAVE_WIN__ALLOCA_FUNC
+            GMIO_HAVE_WIN__ALLOCA_FUNC)
     endif() # WIN32
 endif()
 
diff --git a/src/gmio_core/buffer.c b/src/gmio_core/buffer.c
index 13d88fc..eebb064 100644
--- a/src/gmio_core/buffer.c
+++ b/src/gmio_core/buffer.c
@@ -19,7 +19,7 @@
 
 #if defined(GMIO_HAVE_BSD_ALLOCA_FUNC)
 #  include <alloca.h>
-#elif defined(GMIO_HAVE_WIN_ALLOCA_FUNC)
+#elif defined(GMIO_HAVE_WIN__ALLOCA_FUNC)
 #  include "error.h"
 #  include <windows.h>
 #  include <malloc.h>
@@ -60,7 +60,7 @@ gmio_buffer_t gmio_buffer_alloca(size_t size)
 {
 #if defined(GMIO_HAVE_BSD_ALLOCA_FUNC)
     return gmio_buffer(alloca(size), size, NULL);
-#elif defined(GMIO_HAVE_WIN_ALLOCA_FUNC)
+#elif defined(GMIO_HAVE_WIN__ALLOCA_FUNC)
 #  ifdef _MSC_VER
     __try {
         return gmio_buffer(_alloca(size), size, NULL);
diff --git a/src/gmio_core/config.h.cmake b/src/gmio_core/config.h.cmake
index aa819c3..c91e56d 100644
--- a/src/gmio_core/config.h.cmake
+++ b/src/gmio_core/config.h.cmake
@@ -37,7 +37,7 @@
 #cmakedefine GMIO_HOST_IS_BIG_ENDIAN
 
 #cmakedefine GMIO_HAVE_BSD_ALLOCA_FUNC
-#cmakedefine GMIO_HAVE_WIN_ALLOCA_FUNC
+#cmakedefine GMIO_HAVE_WIN__ALLOCA_FUNC
 
 #if defined(__APPLE__)
 #  if defined(__i386__) || defined(__ppc__)