diff --git a/toonz/sources/common/tsystem/cpuextensions.cpp b/toonz/sources/common/tsystem/cpuextensions.cpp
index 4102cbb1..33a47b45 100644
--- a/toonz/sources/common/tsystem/cpuextensions.cpp
+++ b/toonz/sources/common/tsystem/cpuextensions.cpp
@@ -52,8 +52,8 @@ long __declspec(naked) CPUCheckForExtensions() {
 		push	esi
 		push	ebx
 
-		xor		ebp,ebp			;cpu flags - if we don't have CPUID, we probably
-								;won't want to try FPU optimizations.
+		xor		ebp,ebp			;cpu flags - if we do not have CPUID, we probably
+								;will not want to try FPU optimizations.
 
 		;check for CPUID.
 
diff --git a/toonz/sources/image/mesh/tiio_mesh.h b/toonz/sources/image/mesh/tiio_mesh.h
index 4c56803b..f49cae00 100644
--- a/toonz/sources/image/mesh/tiio_mesh.h
+++ b/toonz/sources/image/mesh/tiio_mesh.h
@@ -49,4 +49,4 @@ private:
   TLevelReaderMesh &operator=(const TLevelReaderMesh &);
 };
 
-#endif TIIO_MESH_H
+#endif  /* TIIO_MESH_H */
diff --git a/toonz/sources/tnzext/tlin/tlin_superlu_wrap.cpp b/toonz/sources/tnzext/tlin/tlin_superlu_wrap.cpp
index 636f5633..0dcf0c5a 100644
--- a/toonz/sources/tnzext/tlin/tlin_superlu_wrap.cpp
+++ b/toonz/sources/tnzext/tlin/tlin_superlu_wrap.cpp
@@ -469,7 +469,7 @@ int sp_dgemv (char *, double, SuperMatrix *, double *,
   SuperMatrix *_A = const_cast<SuperMatrix *>(A);
   double *_x      = const_cast<double *>(x);
 
-  sp_dgemv("N", 1.0, _A, _x, 1, 1.0, y, 1);
+  sp_dgemv((char *)"N", 1.0, _A, _x, 1, 1.0, y, 1);
 }
 
 //---------------------------------------------------------------