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| -rw-r--r-- | runtime/doc/dev_style.txt | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/runtime/doc/dev_style.txt b/runtime/doc/dev_style.txt index 0bc27ced15..d6c465ef91 100644 --- a/runtime/doc/dev_style.txt +++ b/runtime/doc/dev_style.txt @@ -886,6 +886,25 @@ You should use: >c case F: ... +Certain compilers do not recognize an exhaustive enum switch statement as +exhaustive, which causes compiler warnings when there is a return statement in +every case of a switch statement, but no catch-all return statement. To fix +these spurious errors, you are advised to use `UNREACHABLE` after the switch +statement to explicitly tell the compiler that the switch statement always +returns and any code after it is unreachable. For example: >c + + enum { A, B, C } var; + ... + switch (var) { + case A: + return 1; + case B: + return 2; + case C: + return 3; + } + UNREACHABLE; + Return Values ~ Do not needlessly surround the `return` expression with parentheses. |