Assert typed data is external iff actually not in heap.

Assert typed data is external iff actually not in heap.

BUG=
R=asiva@google.com, fschneider@google.com

Committed: https://github.com/dart-lang/sdk/commit/24c51b4eea683265712c6617de91ff1c77bec8ee

[koda, 2015-06-12 18:03:19]

koda@google.com changed reviewers:
+ asiva@google.com

[koda, 2015-06-12 18:03:20]

https://codereview.chromium.org/1182103003/diff/1/runtime/vm/dart_api_impl.cc
File runtime/vm/dart_api_impl.cc (right):

https://codereview.chromium.org/1182103003/diff/1/runtime/vm/dart_api_impl.cc...
runtime/vm/dart_api_impl.cc:3634: if (external) {
This could be written as a single ASSERT(... != ...), but I chose this more
verbose form to get a more helpful failure message.

[siva, 2015-06-12 23:10:16]

lgtm

https://codereview.chromium.org/1182103003/diff/1/runtime/vm/dart_api_impl.cc
File runtime/vm/dart_api_impl.cc (right):

https://codereview.chromium.org/1182103003/diff/1/runtime/vm/dart_api_impl.cc...
runtime/vm/dart_api_impl.cc:3634: if (external) {
On 2015/06/12 18:03:20, koda wrote:
> This could be written as a single ASSERT(... != ...), but I chose this more
> verbose form to get a more helpful failure message.


Should we have a check and an explicit error in Dart_NewExternalTypedData to
make sure nobody creates an external typed data object using a heap pointer.

[koda, 2015-06-12 23:23:29]

https://codereview.chromium.org/1182103003/diff/1/runtime/vm/dart_api_impl.cc
File runtime/vm/dart_api_impl.cc (right):

https://codereview.chromium.org/1182103003/diff/1/runtime/vm/dart_api_impl.cc...
runtime/vm/dart_api_impl.cc:3634: if (external) {
On 2015/06/12 23:10:15, siva wrote:
> On 2015/06/12 18:03:20, koda wrote:
> > This could be written as a single ASSERT(... != ...), but I chose this more
> > verbose form to get a more helpful failure message.
> 
> 
> Should we have a check and an explicit error in Dart_NewExternalTypedData to
> make sure nobody creates an external typed data object using a heap pointer.

Good idea; I'll do it for all the NewExternal* functions and share the code.

[koda, 2015-06-13 00:51:51]

Updated with additional, earlier checks.

With a very large heap, this could slow down debug mode a bit if lots of small
external strings are allocated, but I'm not too worried about it. I'll sleep
better with the checks.

[Florian Schneider, 2015-06-16 09:23:49]

fschneider@google.com changed reviewers:
+ fschneider@google.com

[Florian Schneider, 2015-06-16 09:23:49]

lgtm

[koda, 2015-06-16 12:32:34]

Committed patchset #2 (id:20001) manually as
24c51b4eea683265712c6617de91ff1c77bec8ee (presubmit successful).