diff --git a/Makefile b/Makefile
index 16b0095..2f6890a 100644
--- a/Makefile
+++ b/Makefile
@@ -171,8 +171,18 @@ else ifneq (,$(findstring qnx,$(platform)))
 	#LIBS +=-lpthread
 else ifeq ($(platform), emscripten)
    TARGET := $(TARGET_NAME)_libretro_emscripten.bc
-   fpic := -fPIC
-   SHARED := -shared -Wl,--version-script=$(CORE_DIR)/link.T -Wl
+   HAVE_OPENGL = 0
+   HAVE_OPENGLES3 = 0
+   HAVE_THREADS = 0
+   HAVE_WIFI = 0
+   STATIC_LINKING = 1
+
+   CFLAGS += -msimd128 -ftree-vectorize
+   CXXFLAGS += -msimd128 -ftree-vectorize
+
+   CC = emcc
+   CXX = em++
+   AR = emar
 else ifeq ($(platform), vita)
    TARGET := $(TARGET_NAME)_vita.a
    CC = arm-vita-eabi-gcc
@@ -472,9 +482,15 @@ CXXFLAGS += -D_CRT_SECURE_NO_WARNINGS
 endif
 
 ifeq ($(DEBUG), 1)
+   CFLAGS += -O0 -g
    CXXFLAGS += -O0 -g
 else
-   CXXFLAGS += -O3 -fno-tree-vectorize # -DNDEBUG
+   CFLAGS += -O3 # -DNDEBUG
+   CXXFLAGS += -O3 # -DNDEBUG
+   ifneq ($(platform), emscripten)
+      CFLAGS += -fno-tree-vectorize
+      CXXFLAGS += -fno-tree-vectorize
+   endif
 endif
 
 include Makefile.common
diff --git a/src/libretro/libretro-common/glsm/glsm.c b/src/libretro/libretro-common/glsm/glsm.c
index a70aaf4..310e858 100644
--- a/src/libretro/libretro-common/glsm/glsm.c
+++ b/src/libretro/libretro-common/glsm/glsm.c
@@ -662,18 +662,18 @@ void rglBlendFunc(GLenum sfactor, GLenum dfactor)
  * Core in:
  * OpenGL    : 1.4
  */
-void rglBlendFuncSeparate(GLenum sfactor, GLenum dfactor)
+void rglBlendFuncSeparate(GLenum srcRGB, GLenum dstRGB, GLenum srcAlpha, GLenum dstAlpha)
 {
 #ifdef GLSM_DEBUG
    log_cb(RETRO_LOG_INFO, "glBlendFuncSeparate.\n");
 #endif
    glsm_ctl(GLSM_CTL_IMM_VBO_DRAW, NULL);
    gl_state.blendfunc_separate.used     = true;
-   gl_state.blendfunc_separate.srcRGB   = sfactor;
-   gl_state.blendfunc_separate.dstRGB   = dfactor;
-   gl_state.blendfunc_separate.srcAlpha = sfactor;
-   gl_state.blendfunc_separate.dstAlpha = dfactor;
-   glBlendFunc(sfactor, dfactor);
+   gl_state.blendfunc_separate.srcRGB   = srcRGB;
+   gl_state.blendfunc_separate.dstRGB   = dstRGB;
+   gl_state.blendfunc_separate.srcAlpha = srcAlpha;
+   gl_state.blendfunc_separate.dstAlpha = dstAlpha;
+   glBlendFuncSeparate(srcRGB, dstRGB, srcAlpha, dstAlpha);
 }
 
 /*