[llvm] [lld] [clang] [lldb] [flang] [libcxx] [clang-tools-extra] [libc] [OpenACC] Initial commits to support OpenACC (PR #70234)

[Erich Keane via cfe-commits]

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@@ -0,0 +1,14 @@
+// RUN: %clang -S -### -fopenacc %s 2>&1 | FileCheck %s --check-prefix=CHECK-DRIVER
+// CHECK-DRIVER: "-cc1" {{.*}} "-fopenacc"
+
+// RUN: %clang -S -### -fopenacc -fexperimental-openacc-macro-override=202211 %s 2>&1 | FileCheck %s --check-prefix=CHECK-MACRO-OVERRIDE
+// RUN: %clang -S -### -fopenacc -fexperimental-openacc-macro-override 202211 %s 2>&1 | FileCheck %s --check-prefix=CHECK-MACRO-OVERRIDE
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erichkeane wrote:

We cannot, because this is a 'builtin' macro, overriding it on the command line is essentially UB.  Additionally, this clarifies that it is an experimental patch, which is less likely to be a concern when we remove it in the future.  That is, the intent is to prevent folks from coming to depend on this in the future.

https://github.com/llvm/llvm-project/pull/70234