It was default on Linux. Abandoned for 2 reasons:
* some cross-platform compiler defines `__linux__` even on bare metal
environment (RTL8196 (MIPS big endian soc) for example).
* some compilers do not align functions pointers so that we need to
specify `-falign-functions=n` (where n>1). It's not suitable for
default configuration.
By our measurement, `mrbtest` consumes 400KB less memory. So if your
target machine is memory tight, add the following command-line options
to `GCC` (unfortunately `clang` does not support `-falign-functions`).
`-falign-functions=2 -DMRB_METHOD_TABLE_INLINE`
Now the method tables (in classes/modules and caches) keeps C function
pointers without wrapping in `struct RProc` objects. For the sake of
portability, `mrb_method_t` is represented by the struct and union, but
if the most significant bit of the pointer is not used by the platform,
`mrb_method_t` should be packed in `uintptr_t` to reduce memory usage.
`MRB_METHOD_TABLE_INLINE` is turned on by default for linux.
b72e94f used _etext and _edata to distinguish C string literals from heap allocated strings,
but using _edata, global char arrays may be considered as string literals. to avoid the issue,
we have to use __init_array_start, which might be less portable. you can still use _edata, by
using MRB_NO_INIT_ARRAY_START.
on platforms with _etext and _edata, mruby can distinguish string literals so that it avoids memory allocation to copy them.
for example, on my Linux box (x86 32bit), memory consumed by mrbtest decreased from 8,168,203 to 8,078,848 (reduced 88KB).
Adds following macros:
* MRB_FIXED_STATE_ATEXIT_STACK (not defined by default)
* When defined enables fixed state atexit stack.
* MRB_FIXED_STATE_ATEXIT_STACK_SIZE (default value: 5)
* This macro will be ignored when `MRB_FIXED_STATE_ATEXIT_STACK` isn't defined.
* When `mrb_state_atexit` is called more than this value it will raise runtime error.
According to CONTRIBUTING.md,
Don't use C++ style comments
/* This is the prefered comment style */
Use C++ style comments only for temporary comment e.g. commenting out some code lines.
Yukihiro "Matz" Matsumoto