Issue #3548 describes a bug in the compiler which was fixed by commit
505e50b. But this case wasn't covered by our current tests (obviously)
and the fix in the compiler looks accidental so it's worth adding a
test for it.
Fixes#3548
This patch adds support for listing and setting breakpoints on inlined functions within stripped binaries. It uses a forked version of `debug/gosym` copied from golang.org/x/vuln/internal/vulncheck/internal/gosym which adds support for parsing the inline tree of the pclntab section. Parsing this section requires knowing the offset of the "go:func.*" symbol, which is not present in stripped binaries via the ``.symtab` section so instead, we search the `.noptrdata` section which contains `runtime.moduledatap` which contains the value of that missing symbol, which we then can use to find the inline tree for a given function.
Given all this we parse the inline tree for each function we find, and then add that information the the appropriate `Function` contained in `bi.Functions`, using a relatively empty `Function` struct as what would be the abstract origin.
- fix TestRefreshCurThreadSelGAfterContinueOnceError and TestBadAccess
to work when debugserver has --unmask-signals
- when a fatal signal is received while singlestepping delay its
delivery until the subsequent continue, otherwise debugserver will get
stuck completely (fixes TestNilPtrDerefInBreakInstr)
We have used a goroutine to keep track of some of the expression
evaluation status across target resumes during call injections.
Now that the expression interpreter has been rewritten to use a stack
machine we can move what little state is left into the stack machine
and get rid of the goroutine-and-channel mechanism.
* proc: use stack machine to evaluate expressions
This commit splits expression evaluation into two parts. The first part (in
pkg/proc/evalop/evalcompile.go) "compiles" as ast.Expr into a list of
instructions (defined in pkg/proc/evalop/ops.go) for a stack machine
(defined by `proc.(*evalStack)`).
The second part is a stack machine (implemented by `proc.(*EvalScope).eval`
and `proc.(*EvalScope).evalOne`) that has two modes of operation: in the
main mode it executes inteructions from the list (by calling `evalOne`), in
the second mode it executes the call injection protocol by calling
`funcCallStep` repeatedly until it either the protocol finishes, needs more
input from the stack machine (to set call arguments) or fails.
This approach has several benefits:
- it is now possible to remove the goroutine we use to evaluate expression
and the channel used to communicate with the Continue loop.
- every time we resume the target to execute the call injection protocol we
need to update several local variables to match the changed state of the
target, this is now done at the top level of the evaluation loop instead of
being hidden inside a recurisive evaluator
- using runtime.Pin to pin addresses returned by an injected call would
allow us to use a more natural evaluation order for function calls, which
would solve some bugs #3310, allow users to inspect values returned by a
call injection #1599 and allow implementing some other features #1465. Doing
this with the recursive evaluator, while keeping backwards compatibility
with versions of Go that do not have runtime.Pin is very hard. However after
this change we can simply conditionally change how compileFunctionCall works
and add some opcodes.
* review round 1
* review round 2
Use the trampoline attribute to detect auto-generated code. This fixes
a bug where stepping into a method of a generic type called through an
interface will take the debugger into an auto-generated wrapper that
does not have a dictionary and using next will step out of the wrapper.
Fixes a bug reported on the #delve channel of the gophers slack server.
There is no benefit to having a small part of the freebsd backend
implemented in C, rather than using cgo. While here, add a missing
call to procstat_close and check the return value of
procstat_getpathname.
* enable func call injection on delve for ppc64le
* Function call injection on Delve/ppc64le, modified DWARF encoding and decoding for floating point registers to make floatsum test work
* Function call injection on Delve/ppc64le cleanup
* skip PIE tests for function call injection on other packages
* Address review comments
* accounted for additional skipped PIE tests for function call injection
* Code cleanup and undoing revert of previous commit
* Enable function call injection only on 1.22 and above and some cleanup
* additional cleanup, go fmt run
* Debug function call tests fail on ppc64le/PIE mode adjusted the backup_test_health.md file accordingly
* proc: correctly update local variables after continue
At various point during the execution of the call injection protocol
the process is resumed and the call injection goroutine could migrate
to a different thread, we must make sure to update our local variables
correctly after every point where the target program is resumed.
'fncall122debug_clean' on 'f469a0a5'.
* go.mod: update golang.org/x/tools
Go 1.22 broke golang.org/x/tools/packages
* cmd/dlv: disable TestStaticcheck with go1.22
Go 1.22 is not yet supported by staticcheck.
From the Go specification:
"1. For a nil slice, the number of iterations is 0." [1]
Therefore, an additional nil check for before the loop is unnecessary.
[1]: https://go.dev/ref/spec#For_range
Signed-off-by: Eng Zer Jun <engzerjun@gmail.com>
Miscellaneous non-functional changes to prepare for adding support for
follow-exec mode on Windows:
- removed (*nativeProcess).wait function from Windows backend (unused).
- move close of ptraceDoneChan from release to handlePtraceFuncs, this
makes postExit callable by a function executed by execPtraceFunc.
- change addTarget to detach before creating the target object if we
don't actually want to attach to the child process, also moved the
detach call to (*processGroup).add instead of having one in addTarget
and one in the code that calls (*processGroup).add.
- changed Detach to be a method of TargetGroup/ProcessGroup, the
Windows backend will need access to the process group to call
WaitForDebugEvent.
- moved resume method to processGroup. First all threads stopped at a
breakpoint need to be stepped, then all other threads can be resumed.
This is true also for linux even though it didn't cause the current
tests to fail.
Adds -chan option to the goroutines command to list only the goroutines
running on a specified channel.
Also when printing a variable if it is a channel also print the list of
goroutines that are waiting on it.
- add architecture rule for ppc64le so that incompatible agents don't
pick up the build
- disable PIE tests on linux/ppc64le (the tests claim it doesn't work)
- enable PIE tests on darwin/amd64 now that the entry point calculation
has been fixed
- remove dependency on wget and curl in the test script for linux to
reduce test time
- only install git in the linux test script when we need it
- remove staticcheck from linux/ppc64le builds (it takes almost 5
minutes between installation and execution and makes the test timeout
sometimes)
- drop windows/arm64/tip build, the windows/arm64 build is broken
anyway and since there is only one agent it makes CI runs slow
- drop linux/ppc64le/tip build, there is only one agent, it's slow and
it will always timeout. CI runs in excess of 1h are too long.
If there is no current goroutine when 'next', 'step' or 'stepout' are
used set a condition that the thread ID should stay the same instead.
This makes stepping work for multithreaded C programs or Go programs
that have threads started by cgo code.
Fixes#3262
Add parsing for the new version format with toolchain (X.Y.Z-something)
and simplify internal representation of versions so that revision, beta
version and rc version are all represented on a single field with rc
and beta versions being negative numbers (this limits rc versions to a
maximum of 1000 which will not be a problem in practice).
TestStacktraceGoroutine failed intermittently on freebsd/amd64/go1.20.
This happens because of two windows, in the scheduler (right after
parking a goroutine and just before resuming a parked goroutine) where
a thread is associated with a goroutine but running in the system stack
and there is no systemstack_switch frame to connect the two stacks.
Go1.22 switched to emitting PIE by default and also changed some
details of the PIE implementation. This breaks delve entirely on macOS.
Fix how relocations are handled on macOS.
Adds a waitfor option to 'dlv attach' that waits for a process with a
name starting with a given prefix to appear before attaching to it.
Debugserver on macOS does not support follow-fork mode, but has this
feature instead which is not the same thing but still helps with
multiprocess debugging somewhat.
Show the location expression that will be used to set a suspended
breakpoint in the breakpoints list.
Also change 'target' called without arguments to print a better error
message and 'target follow-exec' without the last argument to print the
state of follow-exec.
