226aaf3547
This commit makes numerous refinements to cosmopolitan memory handling. The default stack size has been reduced from 2mb to 128kb. A new macro is now provided so you can easily reconfigure the stack size to be any value you want. Work around the breaking change by adding to your main: STATIC_STACK_SIZE(0x00200000); // 2mb stack If you're not sure how much stack you need, then you can use: STATIC_YOINK("stack_usage_logging"); After which you can `sort -nr o/$MODE/stack.log`. Based on the unit test suite, nothing in the Cosmopolitan repository (except for Python) needs a stack size greater than 30kb. There are also new macros for detecting the size and address of the stack at runtime, e.g. GetStackAddr(). We also now support sigaltstack() so if you want to see nice looking crash reports whenever a stack overflow happens, you can put this in main(): ShowCrashReports(); Under `make MODE=dbg` and `make MODE=asan` the unit testing framework will now automatically print backtraces of memory allocations when things like memory leaks happen. Bugs are now fixed in ASAN global variable overrun detection. The memtrack and asan runtimes also handle edge cases now. The new tools helped to identify a few memory leaks, which are fixed by this change. This change should fix an issue reported in #288 with ARG_MAX limits. Fixing this doubled the performance of MKDEPS.COM and AR.COM yet again. |
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calls | ||
consts | ||
errfuns | ||
machcalls | ||
consts.sh | ||
errfuns.h | ||
errfuns.sh | ||
g_syscount.S | ||
gen.sh | ||
machcalls.sh | ||
macros.internal.h | ||
README.md | ||
restorert.S | ||
syscall.S | ||
syscalls.sh | ||
systemfive.S | ||
sysv.mk |
SYNOPSIS
System Five Import Libraries
OVERVIEW
Bell System Five is the umbrella term we use to describe Linux, FreeBSD, OpenBSD, and Mac OS X which all have nearly-identical application binary interfaces that stood the test of time, having definitions nearly the same as those of AT&T back in the 1980's.
Cosmopolitan aims to help you build apps that can endure over the course of decades, just like these systems have: without needing to lift a finger for maintenance churn, broken builds, broken hearts.
The challenge to System V binary compatibility basically boils down to numbers. All these systems agree on what services are provided, but tend to grant them wildly different numbers.
We address this by putting all the numbers in a couple big shell scripts, ask the GNU Assembler to encode them into binaries using an efficient LEB128 encoding, unpacked by _init(), and ref'd via extern const. It gives us good debuggability, and any costs are gained back by fewer branches in wrapper functions.z