When the function we are calling is an autogenerated stub (because, for
example, we are calling it through a function pointer) the declaration
line of variables is meaningless and could cause us to discard valid
return arguments.
* proc: start variable visibility one line after their decl line
In most cases variables shouldn't be visible on their declaration line
because they won't be initialized there.
Function arguments are treated as an exception.
This fix is only applied to programs compiled with Go 1.15 or later as
previous versions of Go did not report the correct declaration line for
variables captured by closures.
Fixes#1134
* proc: silence go vet error
* Makefile: enable PIE tests on windows/Go 1.15
* core: support core files for PIEs on windows
* goversion: add Go 1.15 to supported versions
* proc: fix function call injection for Go 1.15
Go 1.15 changed the call injection protocol so that the runtime will
execute the injected call on a different (new) goroutine.
This commit changes the function call support in delve to:
1. correctly track down the call injection state after the runtime
switches to a different goroutine.
2. correctly perform the escapeCheck when stack values can come from
multiple goroutine stacks.
* proc: miscellaneous fixed for call injection under macOS with go 1.15
- create copy of SP in debugCallAXCompleteCall case because the code
used to assume that regs doesn't change
- fix automatic address calculation for function arguments when an
argument has a spurious DW_OP_piece at entry
Instead of rescanning debug_info every time we want to read a function
(either to find inlined calls or its variables) cache the tree of
dwarf.Entry that we would generate and use that.
Benchmark before:
BenchmarkConditionalBreakpoints-4 1 5164689165 ns/op
Benchmark after:
BenchmarkConditionalBreakpoints-4 1 4817425836 ns/op
Updates #1549
Allow changing the value of a string variable to a new literal string,
which requires calling runtime.mallocgc to allocate the string into the
target process.
This means that a command like:
call f("some string")
is now supported.
Additionally the command:
call s = "some string"
is also supported.
Fixes#826
Support for position independent executables (PIE) on the native linux
backend, the gdbserver backend on linux and the core backend.
Also implemented in the windows native backend, but it can't be tested
because go doesn't support PIE on windows yet.
Go 1.10 added inlined calls to debug_info, this commit adds support
for DW_TAG_inlined_call to delve, both for stack traces (where
inlined calls will appear as normal stack frames) and to correct
the behavior of next, step and stepout.
The calls to Next and Frame of stackIterator continue to work
unchanged and only return real stack frames, after reading each line
appendInlinedCalls is called to unpacked all the inlined calls that
involve the current PC.
The fake stack frames produced by appendInlinedCalls are
distinguished from real stack frames by having the Inlined attribute
set to true. Also their Current and Call locations are treated
differently. The Call location will be changed to represent the
position inside the inlined call, while the Current location will
always reference the real stack frame. This is done because:
* next, step and stepout need to access the debug_info entry of
the real function they are stepping through
* we are already manipulating Call in different ways while Current
is just what we read from the call stack
The strategy remains mostly the same, we disassemble the function
and we set a breakpoint on each instruction corresponding to a
different file:line. The function in question will be the one
corresponding to the first real (i.e. non-inlined) stack frame.
* If the current function contains inlined calls, 'next' will not
set any breakpoints on instructions that belong to inlined calls. We
do not do this for 'step'.
* If we are inside an inlined call that makes other inlined
functions, 'next' will not set any breakpoints that belong to
inlined calls that are children of the current inlined call.
* If the current function is inlined the breakpoint on the return
address won't be set, because inlined frames don't have a return
address.
* The code we use for stepout doesn't work at all if we are inside
an inlined call, instead we call 'next' but instruct it to remove
all PCs belonging to the current inlined call.
On macOS, externally linked programs will have an abbrev for
DW_TAG_subprogram without the haschildren flag set. We should handle
this case instead of expecting all DW_TAG_subprogram entries to have
list of children.
Fixes#1034
