From 193daab9889708f7a20ff46efe0fa4b2bf0468d3 Mon Sep 17 00:00:00 2001 From: Russ Cox Date: Wed, 24 Sep 2014 16:55:26 -0400 Subject: cmd/cc, cmd/ld, runtime: disallow conservative data/bss objects In linker, refuse to write conservative (array of pointers) as the garbage collection type for any variable in the data/bss GC program. In the linker, attach the Go type to an already-read C declaration during dedup. This gives us Go types for C globals for free as long as the cmd/dist-generated Go code contains the declaration. (Most runtime C declarations have a corresponding Go declaration. Both are bss declarations and so the linker dedups them.) In cmd/dist, add a few more C files to the auto-Go-declaration list in order to get Go type information for the C declarations into the linker. In C compiler, mark all non-pointer-containing global declarations and all string data as NOPTR. This allows them to exist in C files without any corresponding Go declaration. Count C function pointers as "non-pointer-containing", since we have no heap-allocated C functions. In runtime, add NOPTR to the remaining pointer-containing declarations, none of which refer to Go heap objects. In runtime, also move os.Args and syscall.envs data into runtime-owned variables. Otherwise, in programs that do not import os or syscall, the runtime variables named os.Args and syscall.envs will be missing type information. I believe that this CL eliminates the final source of conservative GC scanning in non-SWIG Go programs, and therefore... Fixes #909. LGTM=iant R=iant CC=golang-codereviews https://golang.org/cl/149770043 --- src/runtime/proc.go | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'src/runtime/proc.go') diff --git a/src/runtime/proc.go b/src/runtime/proc.go index 9b95868594..4bb661b54b 100644 --- a/src/runtime/proc.go +++ b/src/runtime/proc.go @@ -202,6 +202,14 @@ func newP() *p { return new(p) } +func newM() *m { + return new(m) +} + +func newG() *g { + return new(g) +} + func allgadd(gp *g) { if readgstatus(gp) == _Gidle { gothrow("allgadd: bad status Gidle") -- cgit v1.3-5-g9baa