forked from OSchip/llvm-project
bd0bddc1ea
Early adoption of new technologies or adjusting certain code generation/IR optimization thresholds is often available through some cl::opt options (which have unstable surfaces). Specifying such an option twice will lead to an error. ``` % clang -c a.c -mllvm -disable-binop-extract-shuffle -mllvm -disable-binop-extract-shuffle clang (LLVM option parsing): for the --disable-binop-extract-shuffle option: may only occur zero or one times! % clang -c a.c -mllvm -hwasan-instrument-reads=0 -mllvm -hwasan-instrument-reads=0 clang (LLVM option parsing): for the --hwasan-instrument-reads option: may only occur zero or one times! % clang -c a.c -mllvm --scalar-evolution-max-arith-depth=32 -mllvm --scalar-evolution-max-arith-depth=16 clang (LLVM option parsing): for the --scalar-evolution-max-arith-depth option: may only occur zero or one times! ``` The option is specified twice, because there is sometimes a global setting and a specific file or project may need to override (or duplicately specify) the value. The error is contrary to the common practice of getopt/getopt_long command line utilities that let the last option win and the `getLastArg` behavior used by Clang driver options. I have seen such errors for several times. I think the error just makes users inconvenient, while providing very little value on discouraging production usage of unstable surfaces (this goal is itself controversial, because developers might not want to commit to a stable surface too early, or there is just some subtle codegen toggle which is infeasible to have a driver option). Therefore, I suggest we drop the diagnostic, at least before the diagnostic gets sufficiently better support for the overridding needs. Removing the error is a degraded error checking experience. I think this error checking behavior, if desirable, should be enabled explicitly by tools. Users preferring the behavior can figure out a way to do so. Reviewed By: jhenderson, rnk Differential Revision: https://reviews.llvm.org/D120455 |
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| .. | ||
| Inputs | ||
| L-and-l.test | ||
| archive-flattening.test | ||
| arm64-asm.test | ||
| cpu-subtype-matching.test | ||
| create-static-lib.test | ||
| deterministic-library.test | ||
| filelist.test | ||
| help-message.test | ||
| invalid-input-output-args.test | ||
| missing-library-type.test | ||
| no-symbols-warning.test | ||
| universal-bitcode-flattening.test | ||
| universal-bitcode-output.test | ||
| universal-object-flattening.test | ||
| universal-object-output.test | ||
| version.test | ||
| x86_64-asm.test | ||