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llvm-project/clang/test/CodeGenObjCXX/designated-initializers.mm

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[c++20] Implement semantic restrictions for C++20 designated initializers. This has some interesting interactions with our existing extensions to support C99 designated initializers as an extension in C++. Those are resolved as follows: * We continue to permit the full breadth of C99 designated initializers in C++, with the exception that we disallow a partial overwrite of an initializer with a non-trivially-destructible type. (Full overwrite is OK, because we won't run the first initializer at all.) * The C99 extensions are disallowed in SFINAE contexts and during overload resolution, where they could change the meaning of valid programs. * C++20 disallows reordering of initializers. We only check for that for the simple cases that the C++20 rules permit (designators of the form '.field_name =' and continue to allow reordering in other cases). It would be nice to improve this behavior in future. * All C99 designated initializer extensions produce a warning by default in C++20 mode. People are going to learn the C++ rules based on what Clang diagnoses, so it's important we diagnose these properly by default. * In C++ <= 17, we apply the C++20 rules rather than the C99 rules, and so still diagnose C99 extensions as described above. We continue to accept designated C++20-compatible initializers in C++ <= 17 silently by default (but naturally still reject under -pedantic-errors). This is not a complete implementation of P0329R4. In particular, that paper introduces new non-C99-compatible syntax { .field { init } }, and we do not support that yet. This is based on a previous patch by Don Hinton, though I've made substantial changes when addressing the above interactions. Differential Revision: https://reviews.llvm.org/D59754 llvm-svn: 370544
2019-08-31 06:52:55 +08:00
// RUN: %clang_cc1 -triple arm64 %s -verify -emit-llvm -o - -Wno-c99-designator | FileCheck %s
[sema] Fix infinite loop when using a boolean value as designated initializer. For designated indices use the max array size type bitwidth, not the bitwidth of the index value itself. rdar://21942503 llvm-svn: 243343
2015-07-28 07:16:53 +08:00
// expected-no-diagnostics
// Make sure we don't enter an infinite loop (rdar://21942503)
int vals1[] = {
[__objc_yes] = 1,
[__objc_no] = 2
};
// CHECK: @vals1 = global [2 x i32] [i32 2, i32 1]
int vals2[] = {
[true] = 3,
[false] = 4
};
// CHECK: @vals2 = global [2 x i32] [i32 4, i32 3]
int vals3[] = {
[false] = 1,
[true] = 2,
5
};
// CHECK: @vals3 = global [3 x i32] [i32 1, i32 2, i32 5]
int vals4[2] = {
[true] = 5,
[false] = 6
};
// CHECK: @vals4 = global [2 x i32] [i32 6, i32 5]
int vals5[3] = {
[false] = 1,
[true] = 2,
6
};
// CHECK: @vals5 = global [3 x i32] [i32 1, i32 2, i32 6]
[test] Follow-up for r243343, also add a test case using an enum for designated enum. llvm-svn: 243355
2015-07-28 08:01:13 +08:00
enum SomeEnum : unsigned char {
blah = 255
};
char vals6[] = {
[blah] = 'a'
};
// CHECK: @vals6 = global [256 x i8] c"\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00a"