https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70172
Bug ID: 70172
Summary: incorrect reinterpret_cast from integer to pointer
error on invalid constexpr initialization
Product: gcc
Version: 6.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: msebor at gcc dot gnu.org
Target Milestone: ---
The following invalid code is erroneously accepted by 5.x and 4.9.3. It is
rejected by 6.0 but with an obviously incorrect error. The code is invalid not
because of a cast (there is none) but because it attempts to use a null pointer
to form the address of a member of an object.
$ cat ~/tmp/t.c && /build/gcc-trunk/gcc/xgcc -B/build/gcc-trunk/gcc -S -Wall
-Wextra -Wpedantic -xc++ ~/tmp/t.c
struct S { int a, b[1]; };
constexpr S *p1 = (S*)0;
constexpr int *q1 = p1->b;
/home/remote/msebor/tmp/t.c:4:25: error: reinterpret_cast from integer to
pointer
constexpr int *q1 = p1->b;
^
