[SR-3663] Successful '||' ignores rest of expression in conditional compilation directive

[rintaro]

Previous ID	SR-3663
Radar	rdar://21692106
Original Reporter	@rintaro
Type	Bug
Status	Resolved
Resolution	Done

Environment

Xcode Version 8.2.1 (8C1002)
Apple Swift version 3.0.2 (swiftlang-800.0.63 clang-800.0.42.1)
Target: x86_64-apple-macosx10.9

Additional Detail from JIRA

Votes	0
Component/s	Compiler
Labels	Bug, AcceptsInvalid, Parser
Assignee	@rintaro
Priority	Medium

md5: 7097303969b0da5727e851a9bfec453c

relates to:

• SR-3455 Evaluation and Validation of Build Conditions Should Be Separate

Issue Description:

This code compiles, and prints true.

#if false || true && os(99.0) || Whoops (try Anything) is OK?
print(true)
#endif

Even if the syntax is OK, this is evaluated to true

#if false || true && false
print(true)
#endif

Two problems here:

• Precedence of && should be higher than ||.

• Whole syntax should be validated even if || expression is resulted to success.

[belkadan]

*sigh* And of course these would both be source-breaking changes.

[rintaro]

#7955