Makefile: rewrite

* Get rid of useless targets
* Use real recipes instead of command runner targets
* When given, use environment variables
* Document Makefile stuff in doc/build.md

1 files changed, 48 insertions, 0 deletions

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+# Building Chawan
+
+Chawan uses GNU make for builds.
+
+## Variables
+
+Following is a list of variables which may be safely overridden. You can
+also override them by setting an environment variable with the same name.
+
+* `TARGET`: the build target. By default, this is `release`; for development,
+  `debug` is recommended.<br>
+  This variable changes flags passed to the Nim compiler as follows:
+	- `debug`: Generate a debug build, with --debugger:native (embedded
+	  debugging symbols) enabled. This is useful for debugging, but
+	  generates huge and slow executables.
+	- `release`: This is the default target. We use LTO and strip the
+	  final binary.
+	- `release0`: A release build with stack traces enabled. Useful when
+	  you need to debug a crash that needs a lot of processing to manifest.
+	  Note: this does not enable line traces, so you only get the function
+	  name in stack traces.
+	- `release1`: A release build with --debugger:native enabled. May
+	  be useful for profiling with cachegrind, or debugging a release
+	  build with with gdb.
+* `OUTDIR`: where to output the files.
+* `NIMC`: path to the Nim compiler. Note that you need to include the flag
+  for compilation; by default it is set to `nim c`.
+* `OBJDIR`: directory to output compilation artifacts. By default, it is
+  set to `.obj`.<br>
+  You may be able to speed up compilation somewhat by setting it to an
+  in-memory file system.
+* `PREFIX`: installation prefix, by default it is `/usr/local`.
+* `DESTDIR`: directory prepended to `$(PREFIX)`. e.g. we can set it to
+  `/tmp`, so that `make install` installs the binary to the path
+  `/tmp/usr/local/bin/cha`.
+* `MANPREFIX`, `MANPREFIX1`, `MANPREFIX5`: prefixes for the installation of
+  man pages. The default setting expands to `/usr/local/share/man/man1`, etc.
+* `CURLLIBNAME`: Change the name of the libcurl shared object file.
+
+## Phony targets
+
+* `clean`: remove OBJDIR, OUTDIR, and the QuickJS library
+* `manpage`: build man pages
+* `install`: install the `cha` binary, and if man pages were generated,
+  those as well
+* `uninstall`: remove the `cha` binary and Chawan man pages
+* `submodule`: download the submodules required for the browser to build
+  (for those of us who keep forgetting the corresponding git command :)