When linking against a Go shared library, when a global variable
in the main module has a type defined in the shared library, the
linker needs to pull the GC data from the shared library to build
the GC program for the global variable. Currently, this fails
silently, as the shared library file is closed too early and the
read failed (with no error check), causing a zero GC map emitted
for the variable, which in turn causes the runtime to treat the
variable as pointerless.
For now, fix this by keeping the file open. In the future we may
want to use mmap to read from the shared library instead.
Also add error checking. And fix a (mostly harmless) mistake in
size caluculation.
Also remove an erroneous condition for ARM64. ARM64 used to have
a special case to get the addend from the relocation on the
gcdata field. That was removed, but the new code accidentally
returned 0 unconditionally. It's no longer necessary to have any
special case, since the addend is now applied directly to the
gcdata field on ARM64, like on all the other platforms.
Fixes#39927.
This is the second attempt of CL 240462. And this reverts
CL 240616.
Change-Id: I01c82422b9f67e872d833336885935bc509bc91b
Reviewed-on: https://go-review.googlesource.com/c/go/+/240621
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
This reverts CL 240462.
Reason for revert: test fails on PPC64LE.
Updates #39927.
Change-Id: I4f14fd0c36e604a80ae9f2f86d1e643e28945e93
Reviewed-on: https://go-review.googlesource.com/c/go/+/240616
Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
When linking against a Go shared library, when a global variable
in the main module has a type defined in the shared library, the
linker needs to pull the GC data from the shared library to build
the GC program for the global variable. Currently, this fails
silently, as the shared library file is closed too early and the
read failed (with no error check), causing a zero GC map emitted
for the variable, which in turn causes the runtime to treat the
variable as pointerless.
For now, fix this by keeping the file open. In the future we may
want to use mmap to read from the shared library instead.
Also add error checking. And fix a (mostly harmless) mistake in
size caluculation.
Also remove an erroneous condition for ARM64. ARM64 used to have
a special case to get the addend from the relocation on the
gcdata field. That was removed, but the new code accidentally
returned 0 unconditionally. It's no longer necessary to have any
special case, since the addend is now applied directly to the
gcdata field on ARM64, like on all the other platforms.
Fixes#39927.
Change-Id: Iecd32315b326c7059587fdc190e2fa99426e497e
Reviewed-on: https://go-review.googlesource.com/c/go/+/240462
Reviewed-by: Than McIntosh <thanm@google.com>
Reviewed-by: Austin Clements <austin@google.com>
Normally, packages are loaded in dependency order, and if a
Library object is not nil, it is already loaded with the actual
fingerprint. In shared build mode, however, packages may be added
not in dependency order (e.g. go install -buildmode=shared std
adds all std packages before loading them), and it is possible
that a Library's fingerprint is not yet loaded. Skip the check
in this case (when the fingerprint is the zero value).
Fixes#39777.
Change-Id: I66208e92bf687c8778963ba8e33e9bd948f82f3a
Reviewed-on: https://go-review.googlesource.com/c/go/+/239517
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
These functions are compiler generated, and as such are only available
in the internal ABI. Doing this avoids generating an alias symbol.
Doing that avoids confusion between unmangled and mangled type symbols.
Fixes#30768
Change-Id: I197a5ba6403aac11989ffa951dbe35bd0506de91
Reviewed-on: https://go-review.googlesource.com/c/go/+/186077
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
