tahonermann added inline comments.
================
Comment at: clang/include/clang/Basic/DiagnosticSemaKinds.td:147-149
+def ext_vla_cxx_static_assert : ExtWarn<
+ "variable length arrays in C++ are a Clang extension; did you mean to use "
+ "'static_assert'?">, InGroup<VLAUseStaticAssert>;
----------------
I find the "did you mean to use 'static_assert'" phrasing awkward here since it
is highly unlikely that someone intended to write `static_assert(x)` and
instead wrote `int my_assert[x ? 1 : -1]`. Perhaps something like this?
"variable length arrays in C++ are a Clang extension; 'static_assert' can be
used in this case".
================
Comment at: clang/test/SemaCXX/vla-ext-diag.cpp:34
+ off-note {{function parameter 'n' with
unknown value cannot be used in a constant expression}}
+}
----------------
Perhaps add a test where the conditional expression is parenthesized.
int array4[(n ? 1 : -1)];
Adding tests for one side being of size 0 might be useful to demonstrate that
those are not intended to trigger the "use 'static_assert'" diagnostic. I know
some compilers don't diagnose on a size of 0 and so the static assert idiom
generally requires a negative number.
int array5[n ? 1 : 0]; // ok?
CHANGES SINCE LAST ACTION
https://reviews.llvm.org/D156565/new/
https://reviews.llvm.org/D156565
_______________________________________________
cfe-commits mailing list
cfe-commits@lists.llvm.org
https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
