Prior to this commit, the build instructions were encoded in Makefiles
that contained GNU extensions that are unique to GNU Make and
incompatible with older implementations.
Thie commit renames all Makefiles to GNUmakefile which clearly denotes
that the file contains GNU extensions.
GNU Make actually first looks for a GNUmakefile, then makefile, THEN
Makefile so in addition to simply being more correct and portable, it
saves a few unnecessary failed attempts to open the correct build
file.
Prior to this commit, our Makefiles assumed the name of the make program
was simply "make".
Since we use GNU make extensions, this isn't always the case --
operating systems like FreeBSD come with their own implementation named
make which can be incompatible with the extensions used in by tinygo.
To run a compatible make on some of these systems, we have explicitly
call GNU make by running gmake.
This commit changes references to the command "make" to "$(MAKE)" which
is a variable that contains the name of the executable invoked to
process the Makefile.
This allow the Makefiles to be uniformly processed by the same make
program.
This reduces complexity in the compiler without affecting binary sizes
too much.
Cortex-M0: no changes
Linux x64: no changes
WebAssembly: some testcases (calls, coroutines, map) are slightly bigger
This simplifies the ABI a lot and makes future changes easier.
In the future, determining which functions need a context parameter
should be moved from IR generation into an optimization pass, avoiding
the need for recursively scanning the Go SSA.
To support the WebAssembly<->JS barrier, return values also have to be
passed in memory. i64 return values are used by syscall/js, so must be
supported across this ABI barrier.
JavaScript does not support i64 directly, so make sure we pass a pointer
instead which can be read from JavaScript.
This is a temporary workaround which should be removed once JavaScript
supports some form of i64 (probably in the form of BigInt).
