diff options
| author | Jakub Jelinek <jakub@redhat.com> | 2021-01-05 17:17:57 +0100 |
|---|---|---|
| committer | Jakub Jelinek <jakub@redhat.com> | 2021-01-05 17:17:57 +0100 |
| commit | 606f2af1973d5c83877d327cb5adef97c4243a73 (patch) | |
| tree | 8b46777a2e840fe67c20284339fc3f0186527dd6 /gcc/cp/semantics.c | |
| parent | af362af18f405c34840d820143aa3a94f72fce4d (diff) | |
| download | gcc-606f2af1973d5c83877d327cb5adef97c4243a73.zip gcc-606f2af1973d5c83877d327cb5adef97c4243a73.tar.gz gcc-606f2af1973d5c83877d327cb5adef97c4243a73.tar.bz2 | |
c++: Fix ICE with __builtin_bit_cast [PR98469]
On the following testcase we ICE during constexpr evaluation (for warnings),
because the IL has ADDR_EXPR of BIT_CAST_EXPR and ADDR_EXPR case asserts
the result is not a CONSTRUCTOR.
The patch punts on lval BIT_CAST_EXPR folding.
> This change is OK, but part of the problem is that we're trying to do
> overload resolution for an S copy/move constructor, which we shouldn't be
> because bit_cast is a prvalue, so in C++17 and up we should use it to
> directly initialize the target without any implied constructor call.
This version therefore wraps it into a TARGET_EXPR then, it alone fixes
the bug, but I've kept the constexpr.c change too.
2021-01-05 Jakub Jelinek <jakub@redhat.com>
PR c++/98469
* constexpr.c (cxx_eval_constant_expression) <case BIT_CAST_EXPR>:
Punt if lval is true.
* semantics.c (cp_build_bit_cast): Call get_target_expr_sfinae on
the result if it has a class type.
* g++.dg/cpp2a/bit-cast8.C: New test.
* g++.dg/cpp2a/bit-cast9.C: New test.
Diffstat (limited to 'gcc/cp/semantics.c')
| -rw-r--r-- | gcc/cp/semantics.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/gcc/cp/semantics.c b/gcc/cp/semantics.c index 9d2ca30..b448efe 100644 --- a/gcc/cp/semantics.c +++ b/gcc/cp/semantics.c @@ -10761,6 +10761,10 @@ cp_build_bit_cast (location_t loc, tree type, tree arg, tree ret = build_min (BIT_CAST_EXPR, type, arg); SET_EXPR_LOCATION (ret, loc); + + if (!processing_template_decl && CLASS_TYPE_P (type)) + ret = get_target_expr_sfinae (ret, complain); + return ret; } |