[LLVMdev] Is infinite empty loop dead code?

[Joshua Cranmer]

On 11/14/2012 2:22 AM, Shuxin Yang wrote:
> I do some google, I cannot find the answer...
> I check C std, I cannot find answer either.

The C++11 standard explicitly allows compilers to assume that all loops 
will eventually terminate:

[intro.multithread] 24:
The implementation may assume that any thread will eventually do one of 
the following:
— terminate,
— make a call to a library I/O function,
— access or modify a volatile object, or
— perform a synchronization operation or an atomic operation.
[ Note: This is intended to allow compiler transformations such as 
removal of empty loops, even when
termination cannot be proven. —end note ]

I don't know if C11 has a similar statement, but C99 has a statement 
which is ambiguous in this regard (it only refers to a requirement upon 
program termination).

There's a blog post by John Regehr on this topic: 
<http://blog.regehr.org/archives/161>.

-- 
Joshua Cranmer
News submodule owner
DXR coauthor