Suppress warnings for 0-length sequences is not required.
By commit f1a02dff58, it was introduced.
By commit 24939723d7, pseudo-variable length arrays are now used and the warning suppression is no longer needed.
By commit e8841fbf58, moved the intervening code.
The C local variable is not protected from GC, so we use the function
mrb_gc_protect() to keep the value. We also keep the arena position by
mrb_gc_arena_save(), then restoring the position for every new return
value, to minimize arena size.
Small cosmetic changes (pre-increment to post-increment) are also made
in this commit.
When calling `mrb_equal()` or `mrb_funcall()` family functions, the GC arena should be restored if the loop is repeated by a non-immediate return value.
In my opinion, restoring the GC arena is unnecessary when a non-immediate (true) value causes the function to return (e.g. the `mrb_ary_index_m()` function).
The patch does not take into account the case of recursive calls and may be incomplete.
We assumed there's no need for gc_arena_keep() when MRB_GC_FIXED_ARENA
is set. But it turned out that gc_protect() still can cause use-after-free
with fixed arena.
Revert "gc.c (gc_protect): should not call gc_arena_keep twice from allocation"
This reverts commit 28ece4ed8b.
Revert "gc.c (gc_arena_keep): reorganized for MRB_GC_FIXED_ARENA; ref #6329"
This reverts commit 33dd623a02.
“mruby-compiler” should be able to generate `y.tab.c` files through a separate build configuration if it is not added to the ‘host’ build.
In the example above, the “host/mrbc” build should generate the `y.tab.c` file.
When GC occurs during the expansion of the GC arena by `gc_protect()` in `mrb_obj_alloc()`, the object page just allocated by `add_heap()` is released.
Therefore, as soon as control returns from `gc_protect()`, there is a possibility of illegal writing or reading to the address just released.
This issue was discovered during the investigation of #6326.
The following assertions can be added to omit the `if` block
- env object must be non-null
- env object must be in a shared state with the stack
The current caller is believed to satisfy the condition.
A reference to an invalid address might occur in `is_dead()` of `obj_free()` called from `incremental_sweep_phase()`.
This would happen if the heap page was freed ahead of time in the same `incremental_sweep_phase()`.
fixed#6326
If comparing function (block or `<=>`) modifies the sorting array and GC
happens after the modification, objects passed to comparison may be
freed by GC.
The build configuration for `mruby` assumes only the `ncurses` library
needs to be linked because `tinfo` is implicitly pulled in.
In environments where ncurses is available only as a static library,
`tinfo` needs to be linked explicitly (needed for functions like
`tputs`.
This patch fixes that by linking `tinfo` if available.
It also fixes the build for environments where only the `ncursesw`
version of the library (including wide character support) is present,
while still giving preference to the `ncurses` version (without wide
character support).
dearblue