Selectors (GNU Compiler Collection (GCC) Internals)

#### 6.2.2 Selecting targets to which a test applies ¶

Several test directives include selectors to limit the targets for which a test is run or to declare that a test is expected to fail on particular targets.

A selector is:

- one or more target triplets, possibly including wildcard characters; use ‘`*-*-*`’ to match any target
- a single effective-target keyword (see Keywords describing target attributes)
- a list of compiler options that should be included or excluded (as described in more detail below)
- a logical expression

Depending on the context, the selector specifies whether a test is skipped and reported as unsupported or is expected to fail. A context that allows either ‘`target`’ or ‘`xfail`’ also allows ‘`{ target selector1 xfail selector2 }`’ to skip the test for targets that don’t match selector1 and the test to fail for targets that match selector2.

A selector expression appears within curly braces and uses a single logical operator: one of ‘`!`’, ‘`&&`’, or ‘`||`’. An operand is one of the following:

- another selector expression, in curly braces
- an effective-target keyword, such as `lp64`
- a single target triplet
- a list of target triplets within quotes or curly braces
- one of the following:
  ‘`{ any-opts opt1 … optn }`’

    Each of opt1 to optn is a space-separated list of option globs. The selector expression evaluates to true if, for one of these strings, every glob in the string matches an option that was passed to the compiler. For example:

        { any-opts "-O3 -flto" "-O[2g]" }

    is true if any of the following are true:

    - `-O2` was passed to the compiler
    - `-Og` was passed to the compiler
    - both `-O3` and `-flto` were passed to the compiler

    This kind of selector can only be used within `dg-final` directives. Use `dg-skip-if`, `dg-xfail-if` or `dg-xfail-run-if` to skip whole tests based on options, or to mark them as expected to fail with certain options.

  ‘`{ no-opts opt1 … optn }`’

    As for `any-opts` above, each of opt1 to optn is a space-separated list of option globs. The selector expression evaluates to true if, for all of these strings, there is at least one glob that does not match an option that was passed to the compiler. It is shorthand for:

        { ! { any-opts opt1 ... optn } }

    For example:

        { no-opts "-O3 -flto" "-O[2g]" }

    is true if all of the following are true:

    - `-O2` was not passed to the compiler
    - `-Og` was not passed to the compiler
    - at least one of `-O3` or `-flto` was not passed to the compiler

    Like `any-opts`, this kind of selector can only be used within `dg-final` directives.

Here are some examples of full target selectors:

    { target { ! "hppa*-*-* ia64*-*-*" } }
    { target { powerpc*-*-* && lp64 } }
    { xfail { lp64 || vect_no_align } }
    { xfail { aarch64*-*-* && { any-opts "-O2" } } }