Compile at -O2 and disable optimizations that trigger gcc bugs.
Some people still reported mksnapshot crashes after commit b40f813 ("build: fix
spurious mksnapshot crashes for good" - so much for that).
Average performance of the -O2 binary is on par with the -O3 binary. Variance
on the http_simple bytes/8 benchmark appears to be slightly greater but small
enough that the possibly of it being noise cannot be excluded.
The new binary very slightly but consistently outperforms the -O3 binary (by
about 0.5%) on the mostly CPU-bound bytes/102400 benchmark. That could be an
artifact of the system I benchmarked it on, a Core 2 Duo with a puny 32 kB of
L1 instruction cache. The smaller binary seems to play nicer with the cache.
A variety of gcc bugs made mksnapshot crash with either a segmentation fault
or a 'pure virtual method callled' run-time error.
After much wailing and gnashing of teeth I managed to deduce that the bugs
show up when:
1. gcc 4.5.2 for i386-pc-solaris2.11 is used and -fstrict-aliasing is
enabled, or
2. gcc version 4.4.6 for x86_64-redhat-linux is used and
-ffunction-sections -finline-functions at -O2 or higher is enabled
Therefore, disable -ffunction-sections and -fdata-sections unconditionally
and disable -fstrict-aliasing only on Solaris.
The -ffunction-sections and -fdata-sections switches were nonsense anyway
because we don't link with -Wl,--gc-sections.
* compile with -DOPENSSL_NO_SOCK and -DOPENSSL_NO_DGRAM, we don't need it
* compile with -DOPENSSL_NO_GOST and -DOPENSSL_NO_HW_PADLOCK, works around the
brain dead linker on solaris and maybe others
* compile with -DTERMIOS, OS X doesn't have <termio.h>
* compile with -D__EXTENSIONS__ on solaris, makes siginfo_t available
* compile without -ansi on linux, it hides a number of POSIX declarations
(sigaction, NI_MAXHOST, etc.)
* fixes #2110
* includes V8 postmortem metadata in Solaris builds
* adds GYP support for DTrace probes and ustack helper
* ustack helper derives constants dynamically from libv8_base.a
* build with DTrace support by default on SunOS
A compiler bug in older versions of gcc makes it do unsafe optimizations at -O1
and higher. This manifested itself with (at least) gcc 4.5.2 on SmartOS because
it made V8 hang in a busy loop.
See http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45883
Fixes a struct stat size mismatch on 64 bits machines that made Node crash with
a EXC_BAD_ACCESS on startup.
Fixes #2061 for gyp builds. Solution proposed by Paddy Byers.
Hoist common settings into common.gypi.
Restrict v8's common.gypi to v8 projects.
Ensure v8 doesn't use /MP in debug builds.
Add basic settings for other platforms.
Make uv import common.gypi properly.
Remove LTCG warning.
