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C and C++ Implementation Details
5.2 C++ implementation details
This section describes language implementation details specific to C++.
5.2.1 Using the ::operator new function
In accordance with the ISO C++ Standard, the ::operator new(std::size_t) throws an
exception when memory allocation fails rather than raising a signal. If the exception is
not caught, std::terminate() is called.
The compiler option --force_new_nothrow turns all new calls in a compilation into calls
to ::operator new(std::size_t, std::nothrow_t&) or :operator new[](std::size_t,
std::nothrow_t&). However, this does not affect operator new calls in libraries, nor calls
to any class-specific operator new. See --force_new_nothrow, --no_force_new_nothrow
on page 2-57 for more information.
Legacy support
In RVCT v2.0, when the ::operator new function ran out of memory, it raised the signal
SIGOUTOFHEAP, instead of throwing a C++ exception. See ISO C library
implementation definition on page 2-97 in the Libraries and Floating Point Support
Guide.
In the current release, it is possible to install a new_handler to raise a signal and so restore
the RVCT v2.0 behavior.
Note
Do not rely on the implementation details of this behavior, because it might change in
future releases.
5.2.2 Tentative arrays
The ADS v1.2 and RVCT v1.2 C++ compilers enabled you to use tentative, that is,
incomplete array declarations, for example, int a[]. You cannot use tentative arrays
when compiling C++ with the RVCT v2.x compilers or above.
5.2.3 Old-style C parameters in C++ functions
The ADS v1.2 and RVCT v1.2 C++ compilers enabled you to use old-style C
parameters in C++ functions. That is,
void f(x) int x; { }
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