On 5/14/24 13:54, Marek Polacek wrote:
Tested x86_64-pc-linux-gnu, OK to add such a test?
OK.
-- >8 -- Let int8_t x = 127; This DR says that while x++; invokes UB, ++x; does not. The resolution was to make the first one valid. The following test verifies that we don't report any errors in a constexpr context. DR 2855 gcc/testsuite/ChangeLog: * g++.dg/DRs/dr2855.C: New test. --- gcc/testsuite/g++.dg/DRs/dr2855.C | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) create mode 100644 gcc/testsuite/g++.dg/DRs/dr2855.C diff --git a/gcc/testsuite/g++.dg/DRs/dr2855.C b/gcc/testsuite/g++.dg/DRs/dr2855.C new file mode 100644 index 00000000000..b4609ceaa15 --- /dev/null +++ b/gcc/testsuite/g++.dg/DRs/dr2855.C @@ -0,0 +1,16 @@ +// DR 2855, Undefined behavior in postfix increment +// { dg-do compile { target c++14 } } + +using int8_t = signed char; + +constexpr int +f () +{ + int8_t x = 127; + x++; + int8_t z = 127; + ++z; + return x + z; +} + +constexpr int i = f(); base-commit: c290e6a0b7a9de5692963affc6627a4af7dc2411