| Message ID | 20240210224223.2156462-1-polacek@redhat.com |
|---|---|
| State | New |
| Headers | show |
| Series | c++: ICE with reinterpret_cast and switch [PR113545] | expand |
On 2/10/24 17:42, Marek Polacek wrote: > Bootstrapped/regtested on x86_64-pc-linux-gnu, ok for trunk? OK, thanks. > -- >8 -- > Jason, this is the patch you proposed for PR113545. It looks very safe > so I'm posting it here so that it's not forgotten. > > PR c++/113545 > > gcc/cp/ChangeLog: > > * constexpr.cc (cxx_eval_switch_expr): If the condition doesn't reduce > to an INTEGER_CST, consider it non-constant. > > gcc/testsuite/ChangeLog: > > * g++.dg/cpp1y/constexpr-reinterpret3.C: Remove dg-ice. > --- > gcc/cp/constexpr.cc | 10 ++++++++++ > gcc/testsuite/g++.dg/cpp1y/constexpr-reinterpret3.C | 4 +--- > 2 files changed, 11 insertions(+), 3 deletions(-) > > diff --git a/gcc/cp/constexpr.cc b/gcc/cp/constexpr.cc > index 2ebb1470dd5..fa346fe01c9 100644 > --- a/gcc/cp/constexpr.cc > +++ b/gcc/cp/constexpr.cc > @@ -7106,6 +7106,16 @@ cxx_eval_switch_expr (const constexpr_ctx *ctx, tree t, > cond = cxx_eval_constant_expression (ctx, cond, vc_prvalue, > non_constant_p, overflow_p); > VERIFY_CONSTANT (cond); > + if (TREE_CODE (cond) != INTEGER_CST) > + { > + /* If the condition doesn't reduce to an INTEGER_CST it isn't a usable > + switch condition even if it's constant enough for other things > + (c++/113545). */ > + gcc_checking_assert (ctx->quiet); > + *non_constant_p = true; > + return t; > + } > + > *jump_target = cond; > > tree body > diff --git a/gcc/testsuite/g++.dg/cpp1y/constexpr-reinterpret3.C b/gcc/testsuite/g++.dg/cpp1y/constexpr-reinterpret3.C > index 51feb2e558e..adc0b418df9 100644 > --- a/gcc/testsuite/g++.dg/cpp1y/constexpr-reinterpret3.C > +++ b/gcc/testsuite/g++.dg/cpp1y/constexpr-reinterpret3.C > @@ -1,7 +1,5 @@ > // PR c++/113545 > -// { dg-do compile { target c++14 } } > -// Please change the above "dg-do compile" to "dg-do run" when the ICE is resolved. > -// { dg-ice "PR112545 - constexpr function with switch called for reinterpret_cast" } > +// { dg-do run { target c++14 } } > > char foo; > > > base-commit: 93e1559bea434a681208e5e7a21513d7da2844d6 > prerequisite-patch-id: 9dda211bd29817f18d2d46c3c5a7bbe3708cf9f2
diff --git a/gcc/cp/constexpr.cc b/gcc/cp/constexpr.cc index 2ebb1470dd5..fa346fe01c9 100644 --- a/gcc/cp/constexpr.cc +++ b/gcc/cp/constexpr.cc @@ -7106,6 +7106,16 @@ cxx_eval_switch_expr (const constexpr_ctx *ctx, tree t, cond = cxx_eval_constant_expression (ctx, cond, vc_prvalue, non_constant_p, overflow_p); VERIFY_CONSTANT (cond); + if (TREE_CODE (cond) != INTEGER_CST) + { + /* If the condition doesn't reduce to an INTEGER_CST it isn't a usable + switch condition even if it's constant enough for other things + (c++/113545). */ + gcc_checking_assert (ctx->quiet); + *non_constant_p = true; + return t; + } + *jump_target = cond; tree body diff --git a/gcc/testsuite/g++.dg/cpp1y/constexpr-reinterpret3.C b/gcc/testsuite/g++.dg/cpp1y/constexpr-reinterpret3.C index 51feb2e558e..adc0b418df9 100644 --- a/gcc/testsuite/g++.dg/cpp1y/constexpr-reinterpret3.C +++ b/gcc/testsuite/g++.dg/cpp1y/constexpr-reinterpret3.C @@ -1,7 +1,5 @@ // PR c++/113545 -// { dg-do compile { target c++14 } } -// Please change the above "dg-do compile" to "dg-do run" when the ICE is resolved. -// { dg-ice "PR112545 - constexpr function with switch called for reinterpret_cast" } +// { dg-do run { target c++14 } } char foo;