The madvise() declaration should always be compiled on Solaris
to check whether the declaration is good on the environment.
For the purpose, the #if line is unnecessary.
(There was also a trivial typo that the #if was not closed
by #endif and the check always failed with preprocessor error.)
SunC
```
"cont.c", line 24: identifier redeclared: madvise
current : function(pointer to char, unsigned int, int) returning int
previous: function(pointer to void, unsigned int, int) returning int : "/usr/include/sys/mman.h", line 232
```
GCC
```
cont.c:24:12: error: conflicting types for 'madvise'
24 | extern int madvise(caddr_t, size_t, int);
| ^~~~~~~
In file included from cont.c:16:
/usr/include/sys/mman.h:232:12: note: previous declaration of 'madvise' was here
232 | extern int madvise(void *, size_t, int);
| ^~~~~~~
```
On Solaris, madvise(3C) is NOT defined for SUS (XPG4v2) or later,
but MADV_* macros are defined when __EXTENSIONS__ is defined.
This may cause compile error on Solaris 10 with GCC when
"-Werror=implicit-function-declaration" and "-D_XOPEN_SOURCE=600"
are added by configure.
This allows easy differentiation between ABI incompatible platforms like MSWIN64 and MSVCRT-based MINGW32.
This also implicates a distinct rubygem platform which is also "x64-mingw-ucrt".
Although the term "mingw32" is the OS-part for 64 bit systems as well, the "32" is misleading and confusing for many users.
Therefore the new platform string drops the "32" from the OS part to just "mingw".
This conforms to the common practice of windows platform testing per RUBY_PLATFORM=~/mswin|mingw/ .
Find jemalloc header first, then using the found header, try [with
mangle, without mangle] x [no more additional libraries, adding
jemalloc] combination.
It is reported that combination of `--enable-shared --with-jemalloc`
breaks on Debian bullseye (testig). Deeper investigation revealed that
this system's `ld(1)` is patched, to turn `ld --as-needed` on by
default.
This linker flag strips "unnecessary" library dependencies from an
executable. In case of `ruby(1)` (of `--enable-shared`), because
everything is in `libruby.so`, the binary itself doesn't include any
calls to `malloc(3)` at all. So in spite of our explicit `-ljemalloc`
flag, it is ignored. Libc's one is chosen instead.
This is not what we want. Let's force our `ruby(1)` link what we want.
Fixes https://github.com/ruby/ruby/pull/4627
The author would like to acknowledge
Akihiko Odaki <akihiko.odaki@gmail.com> for their contributions.
On darwin we avoid including sys/user.h to avoid a conflict. Previously
we still ended up with PAGE_SIZE being defined because the headers for
system malloc define it. However, when compiling with jemalloc nothing
would define PAGE_SIZE.
This commit changes configure.ac so that we never use the PAGE_SIZE
constant on darwin and to always use the sysconf fallback.
The current fix for PAGE_SIZE macro detection in autoconf does not work
correctly. I see the following output with running configure on Linux:
```
checking PAGE_SIZE is defined... no
```
Linux has PAGE_SIZE macro. This is happening because the macro exists in
sys/user.h and not in the malloc headers.