https://issues.dlang.org/show_bug.cgi?id=23141

          Issue ID: 23141
           Summary: Improve -release switch description
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: enhancement
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: alphaglosined@gmail.com

"man gdc":

-frelease
    Turns on compiling in release mode, which means not emitting runtime
    checks for contracts and asserts.  Array bounds checking is not done for
    @system and @trusted functions, and assertion failures are undefined
    behavior.

    This is equivalent to compiling with the following options:

    gdc -fno-assert -fbounds-check=safe -fno-invariants \
    -fno-postconditions -fno-preconditions -fno-switch-errors

"ldc2 --help"

 --release  - Compile release version, defaulting to disabled
     asserts/contracts/invariants, and bounds checks in
    @safe functions only

But "man dmd" isn't helpful at all:

-release
              Compile release version

Source: https://forum.dlang.org/post/eopmfcglgutxbuunmbns@forum.dlang.org

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