When a deferred function is called directly Next and StepOut should not
step into it.

Fixes #582

Allows quoted substrings in build-flags flag. This fixes a build
problem on windows where the default build flags must contain a space.

Fixes #634 and #638

Detect calls that do not target a function's entrypoint
(i.e, calls to runtime.duffzero and runtime.duffcopy) and
instead step into them directly.  StepInto sets a breakpoint
past the called function's prologue and expects that continue
will hit that breakpoint, but because the call is into the
interior of the function (well past the prologue) this fails.

Fixes #573

This provides a better error message when the user tries to run dlv
debug on a directory that does not contain a main package, when `dlv
exec` is used with a source file.

Additionally the architecture of the executable is checked as suggested
by @alexbrainman in #443.

Fixes #509

* tests: update to cope with go1.7 SSA compiler

* de-vendored golang.org/x/debug/dwarf

We need our own tweaked version

* dwarf/debug/dwarf: always use the entry's name attribute

Using the name attribute leads to better type names as well as fixes
inconsistencies between 1.5, 1.6 and 1.7.

* proc: Updated loadInterface to work with go1.7

go1.7 changed the internal representation of types, removing the string
field from runtime._type.
Updated loadInterface to use the new str field.

This issue is fixed by go 1.7, the test will only run on newer versions
of the compiler.

* proc: bugfix: StepInto can not function when temp bps exist

* terminal,service: auto-continue during next and step

Make dlv call continue automatically when a breakpoint is hit on a
different goroutine during a next or step operation.
Added API hooks to implement the other solution to this problem (cancel
the next/step operation if a different breakpoint is hit).

Fixes #387

If we are unable to correctly guess how a type is serialized in
debug_info let the user specify it directly.

Workaround for #455

* service/api: Removed unused fields of service/api.Function

* proc/eval: Set return variable name to input expression

* all: fine-grained control of loadValue for better variable printing

Makes proc.(*Variable).loadValue loading parameters configurable
through one extra argument of type LoadConfig.
This interface is also exposed through the API so clients can control
how much of a variable delve should read.

* proc: add tests for command-line arguments

adds tests to make sure command-line arguments are passed to Launch() properly

* proc_windows: pass command-line arguments to CreateProcess()

build command-line arguments according to how the standard library does it and pass the command line along to the actual syscall on Windows.

see discussion in #479

* proc: better testing of cmd-line arguments

* proc_windows: fix a possible error-case with passing just 1 argument

previously, the command line pointer passed to sys.CreateProcess was empty, if we had 0 parameters (len(cmd) == 1, as cmd[0] is the executable, so no cmdlineGo would be created, while with any argument it would as len(cmd) > 1). This might cause problems down the road, so make sure we include the command line every time, even if it seems to work without.

* proc: improve testing of command-line arguments

test that arguments with spaces are passed on correctly and DRY failure/success condition checking in the args test

Automatically sets a breakpoint on runtime.startpanic, the function
that gets called by runtime.dopanic when a panic is not recovered.

Implements #317

The go compiler changed and break statements no longer get compiled to
nothing when -N is passed:

https://go-review.googlesource.com/#/c/19848/
https://go-review.googlesource.com/#/c/19854/

Fixes #411

proc.(*Process) methods are not thread safe, multiple clients
connecting simultaneously to a delve server (Issue #383) or a even
a single over-eager client (Issue #408) can easily crash it.
Additionally (Issue #419) calls to client.(*RPCClient).Halt can
crash the server because they can result in calling the function
debug/dwarf.(*Data).Type simultaneously in multiple threads which
will cause it to return incompletely parsed dwarf.Type values.

Fixes #408, #419 (partial)

Moved the code in testvariables2 and testvariables4 into
testvariables3, renamed testvariables3 into testvariables2

- Unlike FunctionEntryToFirstLine can skip the prologue on functions
that are defined on a single line, either because they weren't
formatted or because they were autogenerated
- Can skip the prologue on most functions when setting a breakpoint
with the filename:line syntax

Fixes #396

Implements #368

1. A running goroutine is by definition not parked waiting for a
chan recv
2. The FDE end address is intended to be exclusive, the code
interpreted as inclusive and sometimes ended up setting a breakpoint
on a function other than the current one.

Past the maximum recursion depth maps shouldn't be loaded at all,
adding map children and not loading them breaks assumptions in
the prettyprinter.

Fixes #406

Fixes #370.

Fixes #384

This patch modifies the `step` command to step to the next source line,
stepping into any function encountered along the way.

Fixes #360

Typedefs that resolve to slices are not recorded in DWARF as typedefs
but instead as structs in a way that there is no way to know they
are really slices using debug/dwarf.
Using golang.org/x/debug/dwarf instead this problem is solved and
as a bonus some types are printed with a nicer names: (struct string
→ string, struct []int → []int, etc)

 Fixes #356 and #293

Location specifiers starting with '*' can be followed by any
expression supported by the evaluator.
The expression should evaluate to either an integer (which will be
interpreted as an address) or to a function pointer (which will be
dereferenced to get the function's entry point).

Temp breakpoints should be cleared even if a non-temp breakpoint is
triggered on the same goroutine that the temp breakpoints are set on.

Fixes #305

Prefetch the entire memory of structs and arrays and cache it instead
of issuing readMemory calls only when we get down to primitive types.
This reduces the number of system calls to ptrace that variables makes.

Improves performance in general, greatly improving it in some
particular cases (involving large structs).

Benchmarks without prefetching:
	BenchmarkArray-4         	      10	 132189944 ns/op	   0.06 MB/s
	BenchmarkArrayPointer-4  	       5	 202538503 ns/op	   0.04 MB/s
	BenchmarkMap-4           	     500	   3804336 ns/op	   0.27 MB/s
	BenchmarkGoroutinesInfo-4	      10	 126397104 ns/op
	BenchmarkLocalVariables-4	     500	   2494846 ns/op

Benchmarks with prefetching:
	BenchmarkArray-4         	     200	  10719087 ns/op	   0.76 MB/s
	BenchmarkArrayPointer-4  	     100	  11931326 ns/op	   0.73 MB/s
	BenchmarkMap-4           	    1000	   1466479 ns/op	   0.70 MB/s
	BenchmarkGoroutinesInfo-4	      10	 103407004 ns/op
	BenchmarkLocalVariables-4	    1000	   1530395 ns/op

Improvement factors:
	BenchmarkArray				12.33x
	BenchmarkArrayPointer		16.97x
	BenchmarkMap					 2.59x
	BenchmarkGoroutinesInfo		 1.22x
	BenchmarkLocalVariables		 1.63x

Fixes #341

Fixes #262

Breakpoints are skipped either because:
1. when multiple breakpoints are hit simultaneously only one is
processed
2. a thread hits a breakpoint while another thread is being
singlestepped over the breakpoint.

Additionally fixed a race condition between Continue and tracee
termination.

Fixes #325

recurseLevel value should not be reset when evaluating the contents
of an interface variable

Fixes #316

The concrete type of an interface only contains the abbreviated
package name, we must construct a map from package names to package
paths to be able to resolve the concrete type of an interface.

supported: len, cap, imag, real, complex

Use m[n:] to skip the first n keys of a map
Map indexing is implemented with a linear scan

Implements #61, #122

Pretty print will print them with the format:
chan <element type> <queued elements>/<queue size>

TestStacktraceGoroutine would occasionally fail due to race
conditions in the test itself

Supported operators:

- All (binary and unary) operators between basic types except <-,
++ and -- (includes & to take the address of an expression)
- Comparison operators between supported compound types
- Typecast of integer constants into pointer types
- struct members
- indexing of arrays, slices and strings
- slicing of arrays, slices and strings
- pointer dereferencing
- true, false and nil constants

Implements #116, #117 and #251