diff --git a/lex.ll b/lex.ll
index 7a3db71a..8baa627a 100644
--- a/lex.ll
+++ b/lex.ll
@@ -76,7 +76,7 @@ static int allTokens[] = {
   TOKEN_TASK, TOKEN_TRUE, TOKEN_TYPEDEF, TOKEN_UNIFORM, TOKEN_UNMASKED,
   TOKEN_UNSIGNED, TOKEN_VARYING, TOKEN_VOID, TOKEN_WHILE,
   TOKEN_STRING_C_LITERAL, TOKEN_DOTDOTDOT,
-  TOKEN_FLOAT_CONSTANT, TOKEN_DOUBLE_CONSTANT,
+  TOKEN_FLOAT_CONSTANT,
   TOKEN_INT8_CONSTANT, TOKEN_UINT8_CONSTANT,
   TOKEN_INT16_CONSTANT, TOKEN_UINT16_CONSTANT,
   TOKEN_INT32_CONSTANT, TOKEN_UINT32_CONSTANT,
@@ -152,7 +152,6 @@ void ParserInit() {
     tokenToName[TOKEN_STRING_C_LITERAL] = "\"C\"";
     tokenToName[TOKEN_DOTDOTDOT] = "...";
     tokenToName[TOKEN_FLOAT_CONSTANT] = "TOKEN_FLOAT_CONSTANT";
-    tokenToName[TOKEN_DOUBLE_CONSTANT] = "TOKEN_DOUBLE_CONSTANT";
     tokenToName[TOKEN_INT8_CONSTANT] = "TOKEN_INT8_CONSTANT";
     tokenToName[TOKEN_UINT8_CONSTANT] = "TOKEN_UINT8_CONSTANT";
     tokenToName[TOKEN_INT16_CONSTANT] = "TOKEN_INT16_CONSTANT";
@@ -267,7 +266,6 @@ void ParserInit() {
     tokenNameRemap["TOKEN_STRING_C_LITERAL"] = "\"C\"";
     tokenNameRemap["TOKEN_DOTDOTDOT"] = "\'...\'";
     tokenNameRemap["TOKEN_FLOAT_CONSTANT"] = "float constant";
-    tokenNameRemap["TOKEN_DOUBLE_CONSTANT"] = "double constant";
     tokenNameRemap["TOKEN_INT8_CONSTANT"] = "int8 constant";
     tokenNameRemap["TOKEN_UINT8_CONSTANT"] = "unsigned int8 constant";
     tokenNameRemap["TOKEN_INT16_CONSTANT"] = "int16 constant";
@@ -343,8 +341,6 @@ inline int ispcRand() {
 WHITESPACE [ \t\r]+
 INT_NUMBER (([0-9]+)|(0x[0-9a-fA-F]+)|(0b[01]+))[uUlL]*[kMG]?[uUlL]*
 INT_NUMBER_DOTDOTDOT (([0-9]+)|(0x[0-9a-fA-F]+)|(0b[01]+))[uUlL]*[kMG]?[uUlL]*\.\.\.
-DOUBLE_NUMBER (([0-9]+|(([0-9]+\.[0-9]*?)|(\.[0-9]+)))([eE][-+]?[0-9]+)??)
-HEX_DOUBLE_NUMBER (0x[01](\.[0-9a-fA-F]*)?p[-+]?[0-9]+?)
 FLOAT_NUMBER (([0-9]+|(([0-9]+\.[0-9]*[fF]?)|(\.[0-9]+)))([eE][-+]?[0-9]+)?[fF]?)
 HEX_FLOAT_NUMBER (0x[01](\.[0-9a-fA-F]*)?p[-+]?[0-9]+[fF]?)
 
@@ -442,19 +438,6 @@ L?\"(\\.|[^\\"])*\" { lStringConst(&yylval, &yylloc); return TOKEN_STRING_LITERA
 }
 
 
-
-{DOUBLE_NUMBER} {
-    RT;
-    yylval.doubleVal = atof(yytext);
-    return TOKEN_DOUBLE_CONSTANT;
-}
-
-{HEX_DOUBLE_NUMBER} {
-    RT;
-    yylval.doubleVal = lParseHexFloat(yytext);
-    return TOKEN_DOUBLE_CONSTANT;
-}
-
 {FLOAT_NUMBER} {
     RT;
     yylval.floatVal = (float)atof(yytext);
diff --git a/parse.yy b/parse.yy
index 933a3455..9a2b4fc3 100644
--- a/parse.yy
+++ b/parse.yy
@@ -149,8 +149,7 @@ struct ForeachDimension {
 
 %union {
     uint64_t intVal;
-    float  floatVal;
-    double doubleVal;
+    float floatVal;
     std::string *stringVal;
     const char *constCharPtr;
 
@@ -186,7 +185,7 @@ struct ForeachDimension {
 %token TOKEN_INT64_CONSTANT TOKEN_UINT64_CONSTANT
 %token TOKEN_INT32DOTDOTDOT_CONSTANT TOKEN_UINT32DOTDOTDOT_CONSTANT
 %token TOKEN_INT64DOTDOTDOT_CONSTANT TOKEN_UINT64DOTDOTDOT_CONSTANT
-%token TOKEN_FLOAT_CONSTANT TOKEN_DOUBLE_CONSTANT TOKEN_STRING_C_LITERAL
+%token TOKEN_FLOAT_CONSTANT TOKEN_STRING_C_LITERAL
 %token TOKEN_IDENTIFIER TOKEN_STRING_LITERAL TOKEN_TYPE_NAME TOKEN_NULL
 %token TOKEN_PTR_OP TOKEN_INC_OP TOKEN_DEC_OP TOKEN_LEFT_OP TOKEN_RIGHT_OP
 %token TOKEN_LE_OP TOKEN_GE_OP TOKEN_EQ_OP TOKEN_NE_OP
@@ -328,11 +327,7 @@ primary_expression
     }
     | TOKEN_FLOAT_CONSTANT {
         $$ = new ConstExpr(AtomicType::UniformFloat->GetAsConstType(),
-                           yylval.floatVal, @1);
-    }
-    | TOKEN_DOUBLE_CONSTANT {
-        $$ = new ConstExpr(AtomicType::UniformDouble->GetAsConstType(),
-                           yylval.doubleVal, @1);
+                           (float)yylval.floatVal, @1);
     }
     | TOKEN_TRUE {
         $$ = new ConstExpr(AtomicType::UniformBool->GetAsConstType(), true, @1);
diff --git a/stdlib.ispc b/stdlib.ispc
index 0d5c4efd..6d7ee051 100644
--- a/stdlib.ispc
+++ b/stdlib.ispc
@@ -1559,18 +1559,6 @@ static inline uniform float clamp(uniform float v, uniform float low, uniform fl
     return min(max(v, low), high);
 }
 
-// double
-
-__declspec(safe,cost2)
-static inline double clamp(double v, double low, double high) {
-    return min(max(v, low), high);
-}
-
-__declspec(safe,cost2)
-static inline uniform double clamp(uniform double v, uniform double low, uniform double high) {
-    return min(max(v, low), high);
-}
-
 // int8
 
 __declspec(safe,cost2)