The most significant 32 bits of a 64 bit long return value get passed in the global tempRet0, but this fails when asm.js and/or closure are enabled as tempRet0 was declared again inside the asm closure. This fix exports tempRet0 via an accessor method Runtime.getTempRet0() which is visible with or without optimisations being enabled

Author: fadams

tests/return64bit/test.c

@@ -0,0 +1,6 @@
+
+// This is just a trivial test function, the key bit of interest is that it returns a 64 bit long.
+long long test() {
+    long long x = ((long long)1234 << 32) + 5678;
+    return x;
+}

tests/return64bit/testbind.js

@@ -0,0 +1,18 @@
+// This code represents a simple native JavaScript binding to a test C function
+// that returns a 64 bit long. Notice that the least significant 32 bits are
+// returned in the normal return value, but the most significant 32 bits are
+// returned via the accessor method Runtime.getTempRet0()
+
+var Module = {
+    'noExitRuntime' : true
+};
+
+Module['runtest'] = function() {
+    var low = _test();
+    var high = Runtime.getTempRet0();
+
+    console.log("low = " + low);
+    console.log("high = " + high);
+};
+
+

tests/return64bit/testbindend.js

@@ -0,0 +1,2 @@
+
+})(); // End of self calling lambda used to wrap library.

tests/return64bit/testbindstart.js

@@ -0,0 +1,3 @@
+
+(function() { // Start of self-calling lambda used to avoid polluting global namespace.
+