gcc/libgo at 51835a800d0781a80e674973b04353464e8f8876 - gcc

History

Ian Lance Taylor abd471378c runtime: fix 32-bit malloc for pointers >= 0x80000000 The spans array is allocated in runtime_mallocinit. On a 32-bit system the number of entries in the spans array is MaxArena32 / PageSize, which (2U << 30) / (1 << 12) == (1 << 19). So we are allocating an array that can hold 19 bits for an index that can hold 20 bits. According to the comment in the function, this is intentional: we only allocate enough spans (and bitmaps) for a 2G arena, because allocating more would probably be wasteful. But since the span index is simply the upper 20 bits of the memory address, this scheme only works if memory addresses are limited to the low 2G of memory. That would be OK if we were careful to enforce it, but we're not. What we are careful to enforce, in functions like runtime_MHeap_SysAlloc, is that we always return addresses between the heap's arena_start and arena_start + MaxArena32. We generally get away with it because we start allocating just after the program end, so we only run into trouble with programs that allocate a lot of memory, enough to get past address 0x80000000. This changes the code that computes a span index to subtract arena_start on 32-bit systems just as we currently do on 64-bit systems. From-SVN: r206501		2014-01-09 23:16:56 +00:00
..
config
go	re PR go/59430 (os/user FAILs on Solaris)	2014-01-08 01:08:29 +00:00
runtime	runtime: fix 32-bit malloc for pointers >= 0x80000000	2014-01-09 23:16:56 +00:00
testsuite
aclocal.m4
config.h.in	syscall: Only call varargs libc functions from C code.	2013-11-24 02:38:28 +00:00
configure	go/build: Set GOARCH on arm64 systems.	2014-01-06 19:24:23 +00:00
configure.ac	go/build: Set GOARCH on arm64 systems.	2014-01-06 19:24:23 +00:00
godeps.sh
LICENSE
Makefile.am	re PR go/59430 (os/user FAILs on Solaris)	2014-01-08 01:08:29 +00:00
Makefile.in	re PR go/59430 (os/user FAILs on Solaris)	2014-01-08 01:08:29 +00:00
MERGE	libgo: Update to current Go library.	2013-11-27 01:05:38 +00:00
merge.sh
mksysinfo.sh
PATENTS
README
README.gcc

README

See ../README.

This is the runtime support library for the Go programming language.
This library is intended for use with the Go frontend.

The library has only been tested on GNU/Linux using glibc.  It should
not be difficult to port to other operating systems.

The library has only been tested on x86/x86_64 systems.  It should not
be difficult to port to other architectures.

Directories:

go
  A copy of the Go library from http://golang.org/, with a few
  changes for gccgo.  Notably, the reflection interface is different.

runtime
  Runtime functions, written in C, which are called directly by the
  compiler or by the library.

syscalls
  System call support.

Contributing
============

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