https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70323
Bug ID: 70323
Summary: [6 regression] missing error on integer overflow in
constexpr function result converted to bool
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 program is rejected by GCC 5 with two errors, one due to
each of the two erroneous calls to the constexpr functions. The program is now
accepted by GCC 6.0. The errors are restored when bool is replaced with int.
The first invalid call became accepted as a result of r233878. The second one
sometime last week (after r234169).
$ cat t.c && /build/gcc-trunk/gcc/xgcc -B/build/gcc-trunk/gcc -S -Wall -Wextra
-Wpedantic -o/dev/null -xc++ t.c
constexpr int overflow_if_0 (int i) { return __INT_MAX__ + !i; }
constexpr int overflow_if_1 (int i) { return __INT_MAX__ + i; }
constexpr bool i0_0 = overflow_if_0 (0); // error expected
constexpr bool i0_1 = overflow_if_0 (1);
constexpr bool i1_0 = overflow_if_1 (0);
constexpr bool i1_1 = overflow_if_1 (1); // error expected
$
