[clang] [clang] Fix false positive -Wmissing-field-initializer for anonymous unions (PR #70829)

[Henrik G. Olsson via cfe-commits]

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@@ -4,7 +4,7 @@
 // RUN: %clang_cc1 -std=c++20 %s -verify=cxx20,expected,reorder -Wno-c99-designator -Werror=reorder-init-list -Wno-initializer-overrides
 // RUN: %clang_cc1 -std=c++20 %s -verify=cxx20,expected,override -Wno-c99-designator -Wno-reorder-init-list -Werror=initializer-overrides
 // RUN: %clang_cc1 -std=c++20 %s -verify=cxx20,expected -Wno-c99-designator -Wno-reorder-init-list -Wno-initializer-overrides
-// RUN: %clang_cc1 -std=c++20 %s -verify=cxx20,expected,wmissing -Wmissing-field-initializers -Wno-c99-designator -Wno-reorder-init-list -Wno-initializer-overrides
+// RUN: %clang_cc1 -std=c++20 %s -verify=cxx20,expected,wmissing -Wmissing-field-initializers -Wno-c99-designator -Wno-reorder-init-list -Wno-initializer-overrides -D NON_PEDANTIC
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hnrklssn wrote:

Imo it's clearer to unconditionally compile the same code for each test case, and instead introduce another `-verify` prefix for the diagnostics that aren't emitted by this invocation.

https://github.com/llvm/llvm-project/pull/70829