Summary:
-fno-exceptions does not implicitly attach a nothrow specifier to every operator
new. Even in this mode, non-nothrow new must not return a null pointer. Failure
to allocate memory can be signalled by other means, or just by killing the
program. This behaviour is consistent with the compiler - even with
-fno-exceptions, the generated code never tests for null (and would segfault if
the opeator actually happened to return null).
Reviewers: jordan_rose
CC: cfe-commits
Differential Revision: http://llvm-reviews.chandlerc.com/D1528
llvm-svn: 189452
This is actually required by the C++ standard in
[basic.stc.dynamic.allocation]p3:
If an allocation function declared with a non-throwing
exception-specification fails to allocate storage, it shall return a
null pointer. Any other allocation function that fails to allocate
storage shall indicate failure only by throwing an exception of a type
that would match a handler of type std::bad_alloc.
We don't bother checking for the specific exception type, but just go off
the operator new prototype. This should help with a certain class of lazy
initalization false positives.
<rdar://problem/12115221>
llvm-svn: 166363