[PATCH] D123009: [Sema] Enum conversion warning when one signed and other unsigned.

[Aaron Ballman via Phabricator via cfe-commits]

aaron.ballman added inline comments.


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Comment at: clang/docs/ReleaseNotes.rst:113-114
   by unary operators.
+- ``-Wenum-conversion`` now warns on conversion of signed enum to unsigned enum
+  and unsigned enum to signed enum rather than ``-Wsign-conversion``.
 
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Minor tweak


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Comment at: clang/test/Sema/enum-sign-conversion.c:6-8
+enum X { A,
+         B,
+         C };
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Unrelated formatting change?


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Comment at: clang/test/Sema/enum-sign-conversion.c:14-18
+enum SE1 { N1 = -1 };
+enum SE2 { N2 = -2 };
+// Unsigned unums
+enum UE1 { P1 };
+enum UE2 { P2 };
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The second variants are unused.


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Comment at: clang/test/Sema/enum-sign-conversion.c:37-43
+unsigned f5(enum UE1 E) {
+  return E; // signed-warning {{implicit conversion changes signedness: 'enum UE1' to 'unsigned int'}}
+}
+
+enum UE1 f6(unsigned E) {
+  return E; // signed-warning {{implicit conversion changes signedness: 'unsigned int' to 'enum UE1'}}
+}
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Shouldn't these not warn as well -- the underlying enum type is unsigned?


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D123009/new/

https://reviews.llvm.org/D123009