Avoid using IS_LINUX. Use plain __linux__.

Makefile

@@ -49,7 +49,6 @@ endif
 
 ifneq ($(findstring Linux,$(OS)),)
    LIBS += -lrt
-   DEFINES += -DIS_LINUX
    OBJ += input/linuxraw_input.o
 endif
 
@@ -135,7 +134,6 @@ ifeq ($(SCALER_NO_SIMD), 1)
 endif
 ifeq ($(SCALER_PERF), 1)
    DEFINES += -DSCALER_PERF
-   LIBS += -lrt
 endif
 
 ifeq ($(HAVE_X11), 1)

Makefile.win

@@ -65,6 +65,9 @@ ifeq ($(HAVE_SDL), 1)
    OBJ += gfx/scaler/scaler.o gfx/scaler/pixconv.o gfx/scaler/scaler_int.o gfx/scaler/filter.o
    LIBS += -lSDL
    DEFINES += -ISDL -DHAVE_SDL
+ifeq ($(SCALER_NO_SIMD), 1)
+   DEFINES += -DSCALER_NO_SIMD
+endif
 endif
 
 ifeq ($(HAVE_THREADS), 1)

driver.c

@@ -125,7 +125,7 @@ static const input_driver_t *input_drivers[] = {
 #ifdef GEKKO
    &input_gx,
 #endif
-#ifdef IS_LINUX
+#ifdef __linux__
    &input_linuxraw,
 #endif
    &input_null,

gfx/gfx_common.c

@@ -35,7 +35,7 @@
 #include <ogc/lwp_watchdog.h>
 #endif
 
-#if IS_LINUX
+#ifdef __linux__
 #include <unistd.h>
 #include <errno.h>
 #include <sys/wait.h>