Files
gcc/libstdc++-v3
Jonathan Wakely 32f2b0f328 libstdc++: Fix ambiguous expression in std::array<T, 0>::front() [PR110139]
For 32-bit targets using -pedantic (or using Clang) makes the expression
_M_elems[0] ambiguous.  The overloaded operator[] that we want to call
has a size_t parameter, but 0 is type ptrdiff_t for many ILP32 targets,
so using the implicit conversion from _M_elems to T* and then
subscripting that is also viable.

Change the 0 to (size_type)0 and also make the conversion to T*
explicit, so that's it's not viable here. The latter change requires a
static_cast in data() where we really do want to convert _M_elems to a
pointer.

libstdc++-v3/ChangeLog:

	PR libstdc++/110139
	* include/std/array (__array_traits<T, 0>::operator T*()): Make
	conversion operator explicit.
	(array::front): Use size_type as subscript operand.
	(array::data): Use static_cast to make conversion explicit.
	* testsuite/23_containers/array/element_access/110139.cc: New
	test.

(cherry picked from commit 56001fad4ecc32396beead6644906e3846244b67)
2023-06-06 14:33:47 +01:00
..
2023-01-16 11:52:17 +01:00
2023-01-16 11:52:17 +01:00
2023-06-02 00:21:53 +00:00
2023-01-01 16:20:13 +01:00

file: libstdc++-v3/README

New users may wish to point their web browsers to the file
index.html in the 'doc/html' subdirectory.  It contains brief
building instructions and notes on how to configure the library in
interesting ways.