From 0250ba589bc7b294d3d1372372b79ea0c9c19817 Mon Sep 17 00:00:00 2001 From: Marek Polacek Date: Mon, 6 Aug 2018 16:46:13 +0000 Subject: [PATCH] re PR c++/86767 (continue statements in constexpr functions causes unbounded looping) PR c++/86767 * constexpr.c (cxx_eval_statement_list): Handle continue. * g++.dg/cpp1y/constexpr-86767.C: New test. From-SVN: r263340 --- gcc/cp/ChangeLog | 5 + gcc/cp/constexpr.c | 10 ++ gcc/testsuite/ChangeLog | 5 + gcc/testsuite/g++.dg/cpp1y/constexpr-86767.C | 119 +++++++++++++++++++ 4 files changed, 139 insertions(+) create mode 100644 gcc/testsuite/g++.dg/cpp1y/constexpr-86767.C diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog index 90af73d4810..7cf87f8b68d 100644 --- a/gcc/cp/ChangeLog +++ b/gcc/cp/ChangeLog @@ -1,3 +1,8 @@ +2018-08-06 Marek Polacek + + PR c++/86767 + * constexpr.c (cxx_eval_statement_list): Handle continue. + 2018-08-03 David Malcolm Jonathan Wakely diff --git a/gcc/cp/constexpr.c b/gcc/cp/constexpr.c index 365296d6e3b..79039ff2b79 100644 --- a/gcc/cp/constexpr.c +++ b/gcc/cp/constexpr.c @@ -3950,6 +3950,16 @@ cxx_eval_statement_list (const constexpr_ctx *ctx, tree t, for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i)) { tree stmt = tsi_stmt (i); + /* We've found a continue, so skip everything until we reach + the label its jumping to. */ + if (continues (jump_target)) + { + if (label_matches (ctx, jump_target, stmt)) + /* Found it. */ + *jump_target = NULL_TREE; + else + continue; + } if (TREE_CODE (stmt) == DEBUG_BEGIN_STMT) continue; r = cxx_eval_constant_expression (ctx, stmt, false, diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index 71e3ad7b441..eec7461275d 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,8 @@ +2018-08-06 Marek Polacek + + PR c++/86767 + * g++.dg/cpp1y/constexpr-86767.C: New test. + 2018-08-06 Uros Bizjak * g++.dg/torture/pr86763.C (dg-additional-options): Add -lrt diff --git a/gcc/testsuite/g++.dg/cpp1y/constexpr-86767.C b/gcc/testsuite/g++.dg/cpp1y/constexpr-86767.C new file mode 100644 index 00000000000..2ad71d507d1 --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp1y/constexpr-86767.C @@ -0,0 +1,119 @@ +// PR c++/86767 +// { dg-do compile { target c++14 } } + +constexpr int +fn0 () noexcept +{ + int r = 0; + for (int i = 0; i < 10; ++i) + { + continue; + r++; + for (int j = 0; j < 10; ++j ) + { + } + } + return r; +} +static_assert (fn0 () == 0, ""); + +constexpr int +fn1 () noexcept +{ + int r = 0; + for (int i = 0; i < 10; ++i) + for (int j = 0; j < 10; ++j) + { + continue; + r++; + } + return r; +} +static_assert (fn1 () == 0, ""); + +constexpr int +fn2 () noexcept +{ + int r = 0; + for (int i = 0; i < 10; ++i) + { + continue; + r++; + } + return r; +} +static_assert (fn2 () == 0, ""); + +constexpr int +fn3 () noexcept +{ + int r = 0; + for (int i = 0; i < 10; ++i) + { + continue; + r++; + while (1) + { + } + } + return r; +} +static_assert (fn3 () == 0, ""); + +constexpr int +fn4 () noexcept +{ + for (int i = 0; i < 10; ++i) + { + switch (i) + { + case 5: + return i; + default: + continue; + } + while (1) + { + } + } + return 0; +} +static_assert (fn4 () == 5, ""); + +constexpr int +fn5 () noexcept +{ + for (int i = 0; i < 10; ++i) + { + switch (i) + { + case 0: + case 1: + case 2: + case 3: + case 4: + continue; + default: + return i; + } + while (1) + { + } + } + return 0; +} +static_assert (fn5 () == 5, ""); + +constexpr int +fn6 () noexcept +{ + int r = 0; + for (int i = 0; i < 10; ++i) + { + continue; + for (int j = 0; j < 10; ++j ) + r++; + } + return r; +} +static_assert (fn6 () == 0, ""); -- 2.30.2