diff --git a/src/libprojectM/Common.hpp b/src/libprojectM/Common.hpp
index 25ecafa88..366802ad6 100755
--- a/src/libprojectM/Common.hpp
+++ b/src/libprojectM/Common.hpp
@@ -63,7 +63,7 @@ extern FILE *fmemopen(void *buf, size_t len, const char *pMode);
 
 #ifdef LINUX
 #include <cstdlib>
-#define projectM_isnan isnan
+#define projectM_isnan std::isnan
 #endif
 
 #ifdef EMSCRIPTEN
diff --git a/src/libprojectM/MilkdropPresetFactory/Parser.cpp b/src/libprojectM/MilkdropPresetFactory/Parser.cpp
index 2a68f8f07..bf7c0f985 100755
--- a/src/libprojectM/MilkdropPresetFactory/Parser.cpp
+++ b/src/libprojectM/MilkdropPresetFactory/Parser.cpp
@@ -1410,7 +1410,7 @@ PerFrameEqn * Parser::parse_implicit_per_frame_eqn(std::istream &  fs, char * pa
   PerFrameEqn * per_frame_eqn;
   GenExpr * gen_expr;
 
-  if (fs == NULL)
+  if (fs.fail())
     return NULL;
   if (param_string == NULL)
     return NULL;
@@ -1565,7 +1565,7 @@ InitCond * Parser::parse_per_frame_init_eqn(std::istream &  fs, MilkdropPreset *
 
   if (preset == NULL)
     return NULL;
-  if (fs == NULL)
+  if (fs.fail())
     return NULL;
 
   if ((token = parseToken(fs, name)) != tEq)
@@ -1879,7 +1879,7 @@ int Parser::parse_shapecode(char * token, std::istream &  fs, MilkdropPreset * p
   /* Null argument checks */
   if (preset == NULL)
     return PROJECTM_FAILURE;
-  if (fs == NULL)
+  if (fs.fail())
     return PROJECTM_FAILURE;
   if (token == NULL)
     return PROJECTM_FAILURE;
@@ -2170,7 +2170,7 @@ int Parser::parse_wave(char * token, std::istream &  fs, MilkdropPreset * preset
 
   if (token == NULL)
     return PROJECTM_FAILURE;
-  if (fs == NULL)
+  if (fs.fail())
     return PROJECTM_FAILURE;
   if (preset == NULL)
     return PROJECTM_FAILURE;
@@ -2352,7 +2352,7 @@ int Parser::parse_shape(char * token, std::istream &  fs, MilkdropPreset * prese
   if (token == NULL)
 
     return PROJECTM_FAILURE;
-  if (fs == NULL)
+  if (fs.fail())
     return PROJECTM_FAILURE;
   if (preset == NULL)
     return PROJECTM_FAILURE;