diff --git a/Test/300.frag b/Test/300.frag
index 9be2818b..84db6963 100644
--- a/Test/300.frag
+++ b/Test/300.frag
@@ -1,5 +1,5 @@
 #version 300 es
-
+void nodef1(float f); // ERROR, no default precision
 uniform sampler2D s2D;
 uniform lowp sampler3D s3D;
 uniform samplerCube sCube;
diff --git a/Test/310.frag b/Test/310.frag
index 1db4ca69..25d8d4a4 100644
--- a/Test/310.frag
+++ b/Test/310.frag
@@ -1,5 +1,5 @@
 #version 310 es
-
+highp float nodef3(float); // ERROR, no default precision
 precision mediump float;
 precision highp usampler2D;
 precision highp sampler2D;
diff --git a/Test/baseResults/300.frag.out b/Test/baseResults/300.frag.out
index be58e28d..6835902b 100644
--- a/Test/baseResults/300.frag.out
+++ b/Test/baseResults/300.frag.out
@@ -1,4 +1,5 @@
 300.frag
+ERROR: 0:2: 'float' : type requires declaration of default precision qualifier 
 ERROR: 0:30: 'noperspective' : Reserved word. 
 ERROR: 0:30: 'noperspective' : not supported with this profile: es
 ERROR: 0:31: 'sampler2D' : sampler/image types can only be used in uniform variables or function parameters: bads
@@ -37,7 +38,7 @@ ERROR: 0:148: 'qualifier' : cannot use auxiliary, memory, interpolation, or prec
 ERROR: 0:150: 'early_fragment_tests' : not supported for this version or the enabled extensions 
 ERROR: 0:152: 'imageBuffer' : Reserved word. 
 ERROR: 0:152: '' :  syntax error
-ERROR: 38 compilation errors.  No code generated.
+ERROR: 39 compilation errors.  No code generated.
 
 
 Shader version: 300
diff --git a/Test/baseResults/310.frag.out b/Test/baseResults/310.frag.out
index 5d4c8958..c5823273 100644
--- a/Test/baseResults/310.frag.out
+++ b/Test/baseResults/310.frag.out
@@ -1,5 +1,6 @@
 310.frag
 Warning, version 310 is not yet complete; most version-specific features are present, but some are missing.
+ERROR: 0:2: 'float' : type requires declaration of default precision qualifier 
 ERROR: 0:8: 'origin_upper_left' : not supported with this profile: es
 ERROR: 0:8: 'pixel_center_integer' : not supported with this profile: es
 ERROR: 0:8: 'gl_FragCoord' : identifiers starting with "gl_" are reserved 
@@ -28,7 +29,7 @@ ERROR: 0:102: 'out' : cannot be bool
 ERROR: 0:103: 'image2D' : sampler/image types can only be used in uniform variables or function parameters: imageOut
 ERROR: 0:103: '' : image variables not declared 'writeonly' must have a format layout qualifier 
 ERROR: 0:104: 'out' : cannot be a matrix 
-ERROR: 28 compilation errors.  No code generated.
+ERROR: 29 compilation errors.  No code generated.
 
 
 Shader version: 310
diff --git a/glslang/MachineIndependent/glslang.y b/glslang/MachineIndependent/glslang.y
index 5966940f..c3365643 100644
--- a/glslang/MachineIndependent/glslang.y
+++ b/glslang/MachineIndependent/glslang.y
@@ -811,6 +811,7 @@ parameter_declarator
             parseContext.error($2.loc, "illegal use of type 'void'", $2.string->c_str(), "");
         }
         parseContext.reservedErrorCheck($2.loc, *$2.string);
+        parseContext.precisionQualifierCheck($1.loc, $1);
 
         TParameter param = {$2.string, new TType($1)};
         $$.loc = $2.loc;
@@ -825,7 +826,8 @@ parameter_declarator
         parseContext.arrayDimCheck($2.loc, $1.arraySizes, $3.arraySizes);
 
         parseContext.arraySizeRequiredCheck($3.loc, $3.arraySizes->getSize());
-        parseContext.reservedErrorCheck($2.loc, *$2.string);
+        parseContext.reservedErrorCheck($2.loc, *$2.string);        
+        parseContext.precisionQualifierCheck($1.loc, $1);
 
         $1.arraySizes = $3.arraySizes;
 
@@ -880,6 +882,7 @@ parameter_type_specifier
         $$.param = param;
         if ($1.arraySizes)
             parseContext.arraySizeRequiredCheck($1.loc, $1.arraySizes->getSize());
+        parseContext.precisionQualifierCheck($1.loc, $1);
     }
     ;