diff options
author | trippels <trippels@138bc75d-0d04-0410-961f-82ee72b054a4> | 2015-08-29 18:51:26 +0000 |
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committer | trippels <trippels@138bc75d-0d04-0410-961f-82ee72b054a4> | 2015-08-29 18:51:26 +0000 |
commit | 748c426a1b106499ced440f548743efdde564d4d (patch) | |
tree | 813dae7e59ddb927d2ea8535efd5aa49086dc622 | |
parent | 08bd9c7ad6acfcef822747dfbb6b56e3b92f34a1 (diff) | |
download | gcc-748c426a1b106499ced440f548743efdde564d4d.tar.gz |
Fix c++/67371 (issues with throw in constexpr)
As PR67371 shows gcc currently rejects all throw statements in
constant-expressions, even when they are never executed.
PR c++/67371
* constexpr.c (potential_constant_expression_1): Remove IF_STMT
case. Move label to COND_EXPR case. Remove checking of
SWITCH_STMT_BODY.
git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@227323 138bc75d-0d04-0410-961f-82ee72b054a4
-rw-r--r-- | gcc/cp/ChangeLog | 7 | ||||
-rw-r--r-- | gcc/cp/constexpr.c | 14 | ||||
-rw-r--r-- | gcc/testsuite/g++.dg/cpp1y/constexpr-new.C | 11 | ||||
-rw-r--r-- | gcc/testsuite/g++.dg/cpp1y/constexpr-throw.C | 34 |
4 files changed, 55 insertions, 11 deletions
diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog index b5a3398c8dc..7cbfa6591f1 100644 --- a/gcc/cp/ChangeLog +++ b/gcc/cp/ChangeLog @@ -1,3 +1,10 @@ +2015-08-29 Markus Trippelsdorf <markus@trippelsdorf.de> + + PR c++/67371 + * constexpr.c (potential_constant_expression_1): Remove IF_STMT + case. Move label to COND_EXPR case. Remove checking of + SWITCH_STMT_BODY. + 2015-08-22 Paolo Carlini <paolo.carlini@oracle.com> PR c++/63693 diff --git a/gcc/cp/constexpr.c b/gcc/cp/constexpr.c index 1eacb8be9a4..0ff9b088cc2 100644 --- a/gcc/cp/constexpr.c +++ b/gcc/cp/constexpr.c @@ -4273,15 +4273,6 @@ potential_constant_expression_1 (tree t, bool want_rval, bool strict, return false; return true; - case IF_STMT: - if (!RECUR (IF_COND (t), rval)) - return false; - if (!RECUR (THEN_CLAUSE (t), any)) - return false; - if (!RECUR (ELSE_CLAUSE (t), any)) - return false; - return true; - case DO_STMT: if (!RECUR (DO_COND (t), rval)) return false; @@ -4310,8 +4301,8 @@ potential_constant_expression_1 (tree t, bool want_rval, bool strict, case SWITCH_STMT: if (!RECUR (SWITCH_STMT_COND (t), rval)) return false; - if (!RECUR (SWITCH_STMT_BODY (t), any)) - return false; + /* FIXME we don't check SWITCH_STMT_BODY currently, because even + unreachable labels would be checked. */ return true; case STMT_EXPR: @@ -4592,6 +4583,7 @@ potential_constant_expression_1 (tree t, bool want_rval, bool strict, return false; return true; + case IF_STMT: case COND_EXPR: case VEC_COND_EXPR: /* If the condition is a known constant, we know which of the legs we diff --git a/gcc/testsuite/g++.dg/cpp1y/constexpr-new.C b/gcc/testsuite/g++.dg/cpp1y/constexpr-new.C new file mode 100644 index 00000000000..7241fefc41e --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp1y/constexpr-new.C @@ -0,0 +1,11 @@ +// { dg-do compile { target c++14 } } + +constexpr int *f4(bool b) { + if (b) { + return nullptr; + } else { + return new int{42}; // { dg-error "call to non-constexpr" } + } +} +static_assert(f4(true) == nullptr, ""); +static_assert(f4(false) == nullptr, ""); // { dg-error "non-constant condition" } diff --git a/gcc/testsuite/g++.dg/cpp1y/constexpr-throw.C b/gcc/testsuite/g++.dg/cpp1y/constexpr-throw.C new file mode 100644 index 00000000000..ac90051d5e9 --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp1y/constexpr-throw.C @@ -0,0 +1,34 @@ +// { dg-do compile { target c++14 } } + +constexpr void f1() { + if (false) + throw; +} + +constexpr void f2() { + if (true) + throw; +} // { dg-error "not a constant-expression" } + +constexpr void f3() { + if (false) + ; + else + throw; +}// { dg-error "not a constant-expression" } + +constexpr void f4() { + throw; +}// { dg-error "not a constant-expression" } + +constexpr int fun(int n) { + switch (n) { + case 0: + return 1; + default: + throw; // { dg-error "not a constant-expression" } + } +} + +static_assert(fun(0), ""); +static_assert(fun(1), ""); // { dg-error "non-constant" } |