# Build flavours

Hadrian supports a few predefined _build flavours_, i.e. collections of build
settings that fully define a GHC build (see `src/Flavour.hs`). Users can add their
own build flavours if need be, as described
[here](https://gitlab.haskell.org/ghc/ghc/blob/master/hadrian/doc/user-settings.md#build-flavour).

## Arguments

The following table summarises extra arguments passed to GHC in different build flavours.
There are four groups of arguments: arguments in `hsDefault` are passed to GHC for all Haskell
source files, `hsLibrary` arguments are added when compiling libraries, `hsCompiler`
when compiling the `compiler` library, and `hsGhc` when compiling/linking the GHC program.

<table>
  <tr>
    <th rowspan="3">Flavour</th>
    <th colspan="8">Extra arguments</th>
  </tr>
  <tr>
    <th colspan="2">hsDefault</td>
    <th colspan="2">hsLibrary</td>
    <th colspan="2">hsCompiler</td>
    <th colspan="2">hsGhc</td>
  </tr>
  <tr>
    <th>stage0</td>
    <th>stage1+</td>
    <th>stage0</td>
    <th>stage1+</td>
    <th>stage0</td>
    <th>stage1+</td>
    <th>stage0</td>
    <th>stage1+</td>
  </tr>
  <tr>
    <th>default<br></td>
    <td>-O<br>-H32m<br></td>
    <td>-O2<br>-H32m</td>
    <td></td>
    <td>-haddock</td>
    <td></td>
    <td></td>
    <td></td>
    <td></td>
  </tr>
  <tr>
    <th>quick</td>
    <td>-O0<br>-H64m</td>
    <td>-O0<br>-H64m</td>
    <td></td>
    <td>-O</td>
    <td>-O2</td>
    <td>-O</td>
    <td>-O</td>
    <td></td>
  </tr>
  <tr>
    <th>quick-validate</td>
    <td>-O0<br>-H64m<br>-Werror</td>
    <td>-O0<br>-H64m<br>-Werror</td>
    <td></td>
    <td>-O</td>
    <td>-O2</td>
    <td>-O</td>
    <td>-O</td>
    <td></td>
  </tr>
  <tr>
    <th>quick-debug</td>
    <td>-O0<br>-H64m</td>
    <td>-O0<br>-H64m</td>
    <td></td>
    <td>-O</td>
    <td>-O2</td>
    <td>-O</td>
    <td>-O</td>
    <td>-debug (link)</td>
  </tr>
  <tr>
    <th>quickest</td>
    <td>-O0<br>-H64m</td>
    <td>-O0<br>-H64m</td>
    <td></td>
    <td></td>
    <td>-O</td>
    <td></td>
    <td>-O</td>
    <td></td>
  </tr>
  <tr>
    <th>perf</td>
    <td>-O<br>-H64m</td>
    <td>-O<br>-H64m</td>
    <td></td>
    <td>-O2</td>
    <td>-O2</td>
    <td>-O2</td>
    <td>-O</td>
    <td>-O2</td>
  </tr>
  <tr>
    <th>prof</td>
    <td>-O0<br>-H64m</td>
    <td>-O0<br>-H64m</td>
    <td></td>
    <td>-O</td>
    <td>-O2</td>
    <td>-O</td>
    <td>-O</td>
  </tr>
  <tr>
    <th>bench</td>
    <td>-O<br>-H64m</td>
    <td>-O<br>-H64m</td>
    <td></td>
    <td>-O2</td>
    <td>-O2</td>
    <td>-O0</td>
    <td>-O2</td>
    <td>-O2</td>
  </tr>
  <tr>
    <th>devel1</td>
    <td>-O<br>-H64m</td>
    <td>-O<br>-H64m</td>
    <td></td>
    <td>-dcore-lint</td>
    <td>-O0<br>-DDEBUG</td>
    <td></td>
    <td>-O0<br>-DDEBUG</td>
    <td></td>
  </tr>
  <tr>
    <th>devel2</td>
    <td>-O<br>-H64m</td>
    <td>-O<br>-H64m</td>
    <td></td>
    <td>-dcore-lint</td>
    <td>-O2</td>
    <td>-O0<br>-DDEBUG</td>
    <td></td>
    <td>-O0<br>-DDEBUG</td>
  </tr>
  <tr>
    <th>validate</td>
    <td>-O0<br>-H64m</td>
    <td>-fllvm-fill-undef-with-garbage</td>
    <td></td>
    <td>-O<br>-dcore-lint<br>-dno-debug-output</td>
    <td>-O2<br>-DDEBUG</td>
    <td>-O<br>-dcore-lint<br>-dno-debug-output</td>
    <td>-O</td>
    <td>-O</td>
  </tr>
  <tr>
    <th>slow-validate</td>
    <td>-O0<br>-H64m</td>
    <td>-fllvm-fill-undef-with-garbage</td>
    <td></td>
    <td>-O<br>-dcore-lint<br>-dno-debug-output</td>
    <td>-O2<br>-DDEBUG</td>
    <td>-O<br>-DDEBUG<br>-dcore-lint<br>-dno-debug-output</td>
    <td>-O</td>
    <td>-O</td>
  </tr>
</table>

### LLVM variants

In addition to the above, there are LLVM variants for the flavours `quick`,
`prof`, `perf` and `bench`, available by appending a `-llvm` suffix (i.e.,
`quick-llvm` for the LLVM variant of `quick`). These differ only in that there
is an additional `-fllvm` flag in `hsDefault` when the stage0 compiler is GHC.
See `src/Settings/Flavours/Llvm.hs` for details.

## Ways

Libraries and GHC can be built in different _ways_, e.g. with or without profiling
information. The following table lists ways that are built in different flavours.

<table>
    <tr>
        <th rowspan="2">Flavour</th>
        <th colspan="2">Library ways</th>
        <th colspan="2">RTS ways</th>
        <th colspan="2">Profiled GHC</th>
    </tr>
    <tr>
        <th>stage0</th>
        <th>stage1+</th>
        <th>stage0</th>
        <th>stage1+</th>
        <th>stage0</th>
        <th>stage1+</th>
    </tr>
    <tr>
    <th>default<br>perf<br>prof<br>devel1<br>devel2<br>perf-llvm<br>prof-llvm</td>
    <td>vanilla</td>
    <td>vanilla<br>profiling<br>dynamic</td>
    <td>logging<br>debug<br>threaded<br>threadedDebug<br>threadedLogging
        <br>debugDynamic<br>threadedDynamic<br>threadedDebugDynamic
        <br>loggingDynamic<br>threadedLoggingDynamic
    </td>
    <td>
        logging<br>debug<br>threaded<br>threadedDebug<br>
        threadedLogging<br>threadedProfiling
        <br>debugDynamic<br>threadedDynamic<br>threadedDebugDynamic
        <br>loggingDynamic<br>threadedLoggingDynamic
    </td>
    <td>Only in<br>prof<br>flavour</td>
    <td>Only in<br>prof<br>flavour</td>
</tr>
<tr>
    <th>quick<br>quick-llvm<br>quick-validate<br>quick-debug</th>
    <td>vanilla</td>
    <td>vanilla<br>dynamic</td>
    <td>logging<br>debug<br>threaded<br>threadedDebug<br>threadedLogging
        <br>debugDynamic<br>threadedDynamic<br>threadedDebugDynamic
        <br>loggingDynamic<br>threadedLoggingDynamic
    </td>
    <td>logging<br>debug<br>threaded<br>threadedDebug<br>threadedLogging
        <br>debugDynamic<br>threadedDynamic<br>threadedDebugDynamic
        <br>loggingDynamic<br>threadedLoggingDynamic
    </td>
    <td>No</td>
    <td>No</td>
</tr>
<tr>
    <th>quickest<br>bench</th>
    <td>vanilla</td>
    <td>vanilla</td>
    <td>vanilla<br>threaded</td>
    <td>vanilla<br>threaded</td>
    <td>No</td>
    <td>No</td>
</tr>
</table>