Frog has bug dealing with overflowing hexadecimal literals

[DartBot]

This issue was originally filed by joaopedr...@gmail.com

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What steps will reproduce the problem?

1. Run this program with Frog:
   main() {
    print(0xABADC0DA + 0xABADC0DA);
    print(0xABADC0DA * 0xABADC0DA);
   }
2. Like so: frogsh kast.dart

What is the expected output? What do you see instead?
Expect it to output the same the Dart VM does:
$ dart_release kast.dart
5760582068
8296076440540789156

Instead, we get this:
$ frogsh kast.dart
-2829352524
2001308926266292700

What version of the product are you using? On what operating system?
Dart bleeding edge. Linux manga 3.0.0-13-generic-pae #­22-Ubuntu SMP Wed Nov 2 15:17:35 UTC 2011 i686 i686 i386 GNU/Linux

Please provide any additional information below.

[rakudrama]

Parsing the hex digits uses
   result = (result << 4) + digit;
This causes truncation to 32 bits at the most significant digits when naively translated to JS.
Changing to
   result = (result * 16) + digit;
will result in more values translated correctly, the remaining issue being truncation at the least-significant digits when the value is not represented exactly by a double.

[DartBot]

This comment was originally written by drfibonacci@google.com

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Added Area-Frog, Triaged labels.

[rakudrama]

The overflow when parsing hex literals is fixed at r1912.

The number is still represented as a JavaScript double.
So the VM and forgsh will differ in the result of the product:
2001308926266290000
instead of
2001308926266292700

Created Issue #638 to track the representation problem. Expect that to take much longer to fix.

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Added Fixed label.