the same code as the VIDBUF8 case, so it only worked for depths <= 8.
The 2 directions for copying between VIDBUFs and MEMBUFs worked by using
a Read/Write organization which makes the destination a VIDBUF so the
MEMBUF case was not reached, and the VIDBUF cases have already been fixed.
Fix this by removing "optimizations" for the VIDBUF8 case so that the
MEMBUF case can fall through to the general (non-segmented) case. The
optimizations were to duplicate code for the VIDBUF8 case so as to
avoid 2 multiplications by 1 at runtime. This optimization is not useful
since the multiplications are not in the inner loop.
Remove the same "optimization" for the VIDBUF8S case. It was even less
useful there since it duplicated more to do relatively less.
the file associated with the given file descriptor.
Reviewed by: kib, asomers
Reviewed by: cem, jilles, brooks (they reviewed previous version)
Discussed with: pjd, and many others
Differential Revision: https://reviews.freebsd.org/D14567
There are a few places that use hand crafted versions of the macros
from sys/netinet/in.h making it difficult to actually alter the
values in use by these macros. Correct that by replacing handcrafted
code with proper macro usage.
Reviewed by: karels, kristof
Approved by: bde (mentor)
MFC after: 3 weeks
Sponsored by: John Gilmore
Differential Revision: https://reviews.freebsd.org/D19317
provider grows, GELI will expand automatically and will move the metadata
to the new location of the last sector.
This functionality is turned on by default. It can be turned off with the
-R flag, but it is not recommended - if the underlying provider grows and
automatic expansion is turned off, it won't be possible to attach this
provider again, as the metadata is no longer located in the last sector.
If the automatic expansion is turned off and the underlying provider grows,
GELI will only log a message with the previous size of the provider, so
recovery can be easier.
Obtained from: Fudo Security
from 1.0.0:
Add "continuation" flag, to allow multiple "xo" invocations in a single line of output (#58)
Add --top-wrap to make top-level JSON wrappers
Add --{open,close}-{list,instace} options
Add xo_xml_leader(), to detect use of some bogus XML tags. It's still bad form, but it's a little safer now
Avoid call to xo_write before xo_flush, since the latter calls the former
Check return code from xo_flush_h properly (<0) (FreeBSD Bug 236935)
For JSON output, avoid newline before a container's close brace (#62)
Merge branch 'text_only' of https://github.com/zvr/libxo into zvr-text_only
Use XO_USE_INT_RETURN_CODES, not USE_INT_RETURN_CODES
add docs for --continuation
add docs for --not-first
call xo_state_set_flags before values and close containers; add XOIF_MADE_OUTPUT flag to track state; make proper empty JSON objects in xo_finish
color_map code has to be #ifdef'd out, since the struct definition
correct xo_flush_func_t (doesn't use xo_ssize_t)
make depth change for --top-wrap only for JSON
fix to handle --top-wrap in "xo" by being more consistent with handling trailing newlines
fix to handle text-only version #64 (from zvr)
fix xo_buf_has_room for round up to the next XO_BUFSIZ, not just add XO_BUFSIZ to the size (FreeBSD Bug 236937)
update docs for new "xo" options
update functions to use xo_ssize_t
update test cases
from 1.0.1:
Add EINTEGRITY to .pot files under test/gettext/ (fix from FreeBSD)
from 1.0.2:
handle failure from xo_vnsprintf; don't add -1 to "rc"
PR: 236937, 236935
Submitted by: phil
Reported by: Alfonso S. Siciliano <alfix86@gmail.com>
MFC after: 2 weeks
To use bectl in an example, when one creates a new boot environment with
either `bectl create <be>` or `bectl create -e <otherbe> <be>`, libbe will
take a snapshot of the original boot environment to clone. Previously, this
used %F-%T date format as the snapshot name, but this has some limitations-
attempting to create multiple boot environments in quick succession may
collide if done within the same second.
Tack a serial onto it to reduce the chances of a collision... we could still
collide if multiple processes/threads are creating boot environments at the
same time, but this is likely not a big concern as this has only been
reported as occurring in freebsd-ci setup.
MFC after: 3 days
The current approach of injecting manifest into mac_veriexec is to
verify the integrity of it in userspace (veriexec (8)) and pass its
entries into kernel using a char device (/dev/veriexec).
This requires verifying root partition integrity in loader,
for example by using memory disk and checking its hash.
Otherwise if rootfs is compromised an attacker could inject their own data.
This patch introduces an option to parse manifest in kernel based on envs.
The loader sets manifest path and digest.
EVENTHANDLER is used to launch the module right after the rootfs is mounted.
It has to be done this way, since one might want to verify integrity of the init file.
This means that manifest is required to be present on the root partition.
Note that the envs have to be set right before boot to make sure that no one can spoof them.
Submitted by: Kornel Duleba <mindal@semihalf.com>
Reviewed by: sjg
Obtained from: Semihalf
Sponsored by: Stormshield
Differential Revision: https://reviews.freebsd.org/D19281
This patch adds a new table begemotSnmpdTransInetTable that uses the
InetAddressType textual convention and can be used to create listening
ports for IPv4, IPv6, zoned IPv6 and based on DNS names. It also supports
future extension beyond UDP by adding a protocol identifier to the table
index. In order to support this gensnmptree had to be modified.
Submitted by: harti
MFC after: 1 month
Relnotes: yes
Differential Revision: https://reviews.freebsd.org/D16654
Per the upstream pull-request [1]:
```
gtest prior to this change would completely ignore `GTEST_SKIP()` if
called in `Environment::SetUp()`, instead of bailing out early, unlike
`Test::SetUp()`, which would cause the tests themselves to be skipped.
The only way (prior to this change) to skip the tests would be to
trigger a fatal error via `GTEST_FAIL()`.
Desirable behavior, in this case, when dealing with
`Environment::SetUp()` is to check for prerequisites on a system
(example, kernel supports a particular featureset, e.g., capsicum), and
skip the tests. The alternatives prior to this change would be
undesirable:
- Failing sends the wrong message to the test user, as the result of the
tests is indeterminate, not failed.
- Having to add per-test class abstractions that override `SetUp()` to
test for the capsicum feature set, then skip all of the tests in their
respective SetUp fixtures, would be a lot of human and computational
work; checking for the feature would need to be done for all of the
tests, instead of once for all of the tests.
For those reasons, making `Environment::SetUp()` handle `GTEST_SKIP()`,
by not executing the testcases, is the most desirable solution.
In order to properly diagnose what happened when running the tests if
they are skipped, print out the diagnostics in an ad hoc manner.
Update the documentation to note this change and integrate a new test,
gtest_skip_in_environment_setup_test, into the test suite.
This change addresses #2189.
Signed-off-by: Enji Cooper <yaneurabeya@gmail.com>
```
The goal with my merging in this change is to avoid requiring extensive
refactoring/retesting of test suites when ensuring prerequisites are met,
e.g., checking for a CAPABILITIES-enabled kernel before running capsicum-test
(see D19758 for more details).
The proof-of-concept is being imported before accepted by the upstream
project due to the fact that the upstream project is undergoing a potential
development freeze and the maintainers aren't responding to my PR.
1. https://github.com/google/googletest/pull/2203
Reported by: asomers (https://github.com/google/googletest/issues/2189)
Reviewed by: asomers
Approved by: emaste (mentor)
MFC after: 2 months
Differential Revision: https://reviews.freebsd.org/D19765
'be_destroy' can destroy a boot environment (by name) or a given snapshot.
If the target to be destroyed is a dataset, check if it's mounted. We don't
want to check if the origin dataset is mounted when destroying a snapshot.
PR: 236043
Submitted by: Rob Fairbanks <rob.fx907 gmail com>
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D19650
The current logic for CSTD/CXXSTD requires homogenity as far as the
supported C/C++ standards, which is a sensible default. However, when
dealing with differing versions of C++, some code may compile with C++11, but
not C++17 (for instance). So in order to avoid having people convert over their
code to the new standard, give the users the ability to specify the standard on
a per-program basis.
This will allow a user to override the supporting standard for a set of
programs, mixing C++11 with C++14 (for instance).
Reviewed by: asomers
Apprved by: emaste (mentor)
MFC after: 1 month
MFC with: r345708
Differential Revision: https://reviews.freebsd.org/D19738
CXXSTD was added as the C++ analogue to CSTD.
CXXSTD defaults to `-std=c++11` with supporting compilers; `-std=gnu++98`,
otherwise for older versions of g++.
This change standardizes the CXXSTD variable, originally added to
googletest.test.inc.mk as part of r345203.
As part of this effort, convert all `CXXFLAGS+= -std=*` calls to use `CXXSTD`.
Notes:
This value is not sanity checked in bsd.sys.mk, however, given the two
most used C++ compilers on FreeBSD (clang++ and g++) support both modes, it is
likely to work with both toolchains. This method will be refined in the future
to support more variants of C++, as not all versions of clang++ and g++ (for
instance) support C++14, C++17, etc.
Any manual appending of `-std=*` to `CXXFLAGS` should be replaced with CXXSTD.
Example:
Before this commit:
```
CXXFLAGS+= -std=c++14
```
After this commit:
```
CXXSTD= c++14
```
Reviewed by: asomers
Approved by: emaste (mentor)
MFC after: 1 month
MFC with: r345203, r345704, r345705
Relnotes: yes
Tested with: make tinderbox
Differential Revision: https://reviews.freebsd.org/D19732
When a review is closed via Phabricator it updates the patch attached to the
review. I downloaded the raw patch from Phabricator, applied it, and repeated
my mistake from r345704 by accident mixing content from D19732 and D19738.
For my own personal sanity, I will try not to mix reviews like this in the
future.
MFC after: 1 month
MFC with: r345706
Approved by: emaste (mentor, implicit)
CXXSTD was added as the C++ analogue to CSTD.
CXXSTD defaults to `-std=c++11` with supporting compilers; `-std=gnu++98`,
otherwise for older versions of g++.
This change standardizes the CXXSTD variable, originally added to
googletest.test.inc.mk as part of r345203.
As part of this effort, convert all `CXXFLAGS+= -std=*` calls to use `CXXSTD`.
Notes:
This value is not sanity checked in bsd.sys.mk, however, given the two
most used C++ compilers on FreeBSD (clang++ and g++) support both modes, it is
likely to work with both toolchains. This method will be refined in the future
to support more variants of C++, as not all versions of clang++ and g++ (for
instance) support C++14, C++17, etc.
Any manual appending of `-std=*` to `CXXFLAGS` should be replaced with CXXSTD.
Example:
Before this commit:
```
CXXFLAGS+= -std=c++14
```
After this commit:
```
CXXSTD= c++14
```
Reviewed by: asomers
Approved by: emaste (mentor)
MFC after: 1 month
MFC with: r345203, r345704, r345705
Relnotes: yes
Tested with: make tinderbox
Differential Revision: https://reviews.freebsd.org/D19732
I accidentally committed code from two reviews. I will reintroduce the code to
bsd.progs.mk as part of a separate commit from r345704.
Approved by: emaste (mentor, implicit)
MFC after: 2 months
MFC with: r345704
CXXSTD defaults to `-std=c++11` with supporting compilers; `-std=gnu++98`,
otherwise for older versions of g++.
This change standardizes the CXXSTD variable, originally added to
googletest.test.inc.mk as part of r345203.
As part of this effort, convert all `CXXFLAGS+= -std=*` calls to use `CXXSTD`.
Notes:
This value is not sanity checked in bsd.sys.mk, however, given the two
most used C++ compilers on FreeBSD (clang++ and g++) support both modes, it is
likely to work with both toolchains. This method will be refined in the future
to support more variants of C++, as not all versions of clang++ and g++ (for
instance) support C++14, C++17, etc.
Any manual appending of `-std=*` to `CXXFLAGS` should be replaced with CXXSTD.
Example:
Before this commit:
```
CXXFLAGS+= -std=c++14
```
After this commit:
```
CXXSTD= c++14
```
Reviewed by: asomers
Approved by: emaste (mentor)
MFC after: 1 month
Relnotes: yes
Differential Revision: https://reviews.freebsd.org/D19732
If dso uses initial exec TLS mode, rtld tries to allocate TLS in
static space. If there is no space left, the dlopen(3) fails. If space
if allocated, initial content from PT_TLS segment is distributed to
all threads' pcbs, which was missed and caused un-initialized TLS
segment for such dso after dlopen(3).
The mode is auto-detected either due to the relocation used, or if the
DF_STATIC_TLS dynamic flag is set. In the later case, the TLS segment
is tried to allocate earlier, which increases chance of the dlopen(3)
to succeed. LLD was recently fixed to properly emit the flag, ld.bdf
did it always.
Initial test by: dumbbell
Tested by: emaste (amd64), ian (arm)
Tested by: Gerald Aryeetey <aryeeteygerald_rogers.com> (arm64)
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
Differential revision: https://reviews.freebsd.org/D19072
Correct restoring was only attempted for mode 258 (800x600x4 P). (This
was the only useful graphics mode supported in the kernel until 10-15
years ago, and is still the only one explicitly documented in the man
page). The comment says that it is the geometry (subscreen size) that
is restored, but it seems to only be necessary to restore the font
size, with the geometry only needed since it is set by the same ioctl.
The font size was not restored for this mode, but was forced to 16.
For other graphics modes, the font size was clobbered to 0. This
confuses but doesn't crash the kernel (font size 0 gives null text).
This confuses and crashes vidcontrol. The only way to recover was to
use vidcontrol to set the mode to any text mode on the way back to the
original graphics mode.
vidcontrol gets this wrong in the opposite way when backing out of
changes after an error. It restores the font size correctly, but
forces the geometry to the full screen size.
r80270 has the usual wrong fix for unsafe signal handling -- just set
a flag and return to let an event loop check the flag and do safe
handling. This never works for signals like SIGBUS and SIGSEGV that
repeat and works poorly for others unless the application has an event
loop designed to support this.
For these signals, clean up unsafely as before, except for arranging that
nested signals are fatal and forcing a nested signal if the cleanup doesn't
cause one.
method as in /bin/sh.
We still do technically undefined things in the signal handler, but it
is safe in practice to access state that is protected by INTOFF/INTON.
In a recent commit, I sprinkled VGLMouseFrozen++/-- operations in
places that need INTOFF/INTON. This prevented clobbering of pixels
under the mouse, but left mouse signals deferred for too long. It is
necessary to call the signal handler when the count goes to 0. Old
versions did this in the unfreeze function, but didn't block actual
signals, so the signal handler raced itself. The sprinkled operations
reduced the races, but when then worked to block a race they left
signals deferred for too long.
Use INTOFF/INTON to fix complete loss of mouse signals while reading
the mouse status. Clobbering of the state was prevented by SIG_IGN'ing
mouse signals, but that has a high overhead and broke more than it
fixed by losing mouse signals completely. sigprocmask() works to block
signals without losing them completely, but its overhead is also too
high.
libvgl's mouse signal handling is often worse than none. Applications
can't block waiting for a mouse or keyboard or other event, but have
to busy-wait. The SIG_IGN's lost about half of all mouse events while
busy-waiting for mouse events.
It started truncating its color arg to 8 bits using plot() in r229415.
The version in r229415 is also more than 3 times slower in segmented
modes, by doing more syscalls to move the window.
segmented modes.
Also fix some style bugs in the 2 changed lines. libvgl uses a very non-KNF
style with 2-column indentation with no tabs except for regressions.
r345620 by kib@ fixed the rtld issue that caused a crash at startup
during resolution of libc's ifuncs with BIND_NOW.
PR: 233333
Sponsored by: The FreeBSD Foundation
r322369's use of basename(3) was incorrect and worked by accident so
long as the pidfile path was absolute or consisted of a single
component. Fix the basename() usage and add a regression test.
Reported by: 0mp
Reviewed by: cem
MFC after: 3 days
Differential Revision: https://reviews.freebsd.org/D19728
Reading of single pixels didn't look under the cursor.
Copying of 1x1 bitmaps didn't look under the cursor for either reading
or writing.
Copying of larger bitmaps looked under the cursor for at most the
destination.
Copying of larger bitmaps looked under a garbage cursor (for the Display
bitmap) when the destination is a MEMBUF. The results are not used, so
this only wasted time and flickered the cursor.
Writing of single pixels looked under a garbage cursor for MEMBUF
destinations, as above except this clobbered the current cursor and
didn't update the MEMBUF. Writing of single pixels is not implemented
yet in depths > 8. Otherwise, writing of single pixels worked. It was
the only working case for accessing pixels under the cursor.
Clearing of MEMBUFs wasted time freezing the cursor in the Display bitmap.
The fixes abuse the top bits in the color arg to the cursor freezing
function to control the function. Also clear the top 8 bits so that
applications can't clobber the control bits or create 256 aliases for
every 24-bit pixel value in depth 32.
Races fixed:
Showing and hiding the cursor only tried to avoid races with the mouse
event signal handler for internal operations. There are still many
shorter races from not using volatile or sig_atomic_t for the variable
to control this. This variable also controls freezes, and has more
complicated states than before.
The internal operation of unfreezing the cursor opened a race window
by unsetting the signal/freeze variable before showing the cursor.
depths for the source and target are not supported. The bits for higher
numbered planes (mostly for red) were either not copied or were copied to
lower numbered planes for nearby pixels.
Quick fix for creation of mouse cursor bitmaps in all depths. This fix is
only complete for the default lightwhite cursor with a black frame.
Even the lightwhite and black colors are hard to find. The templates
use 0xff for lightwhite, but that means brightblue in the simplest mode
(Truecolor depth 24). Other modes are even more complicated -- they are
singly or doubly indirect throught palette(s) and changing of the palettes
by applications is supported.
Details:
Replicate the template value for Truecolor modes to fill out the target
depth (and more for depths not a multiple of 8). Do this for every
drawing of the cursor so that it sort of works for mouse cursor bitmaps
set by applications.
Use 0xf for lightwhite in most other modes. Only do this for the
default cursor so that it doesn't affect mouse cursor bitmaps set by
applications. 0xf mostly works because it was originally for CGA
lightwhite and is emulated using 1 or 2 indirections on EGA and VGA.
0x3f (EGA white) and 0xff (VGA black) direct palette indexes mostly
don't work since backwards compatibility inhibits or prevents them
representing lightwhite. But 0x3f (EGA white) must be used for mode
37 (VGA_MODEX) (320x240x8 V) since this mode is closer to EGA than VGA.
was not taken modulo the window size in VGLClear().
Segmented modes also need a kernel fix to almost work. The ioctl to set
the window origin is broken.
These bugs are rarely problems since non-VESA modes only need
segmentation to support multiple pages but libvgl doesn't support
multiple pages and treats these modes as non-segmented, and VESA modes
are usually mapped linearly except on old hardware so they really are
non-segmented.
to match the change in its declaration. Change the declaration back to
"byte color" since setting of the border color is not supported for more
than 256 colors.
VGLBitmapString() and VGLSetBorder() so as to not truncate to 8 bits.
Complete the corresponding fix for VGLGetXY() and VGLPutXY() (parts
of the man page were out of date).
Since the font format is undocumented, it is unclear how non-multiples
of 8 should be padded to bytes in the font file. Use the same
representation as bdf text format (big- endian, with padding in the
lower bits).
There seems to be no alternative to reading each plane independently using
3 slow i/o's per plane (this delivers 8 nearby pixels, but we don't buffer
the results so run 8 times slower than necessary.
All the code for this was there, but it was ifdefed out and replaced by
simpler code that cannot work in planar modes. The ifdefed out code
was correct except it was missing a volatile declaration, so compilers
optimized the multiple dummy reads in it to a single read.
Support for 16-bit and 32-bit Truecolor modes was supposed to be
complete in r70991 of main.c and in nearby revisions for other files, but
it was broken by the overruns in most cases (all cases were the mouse
is enabled, and most cases where bitmaps are used). r70991 also
uninintentionally added support for depths 9-15, 17-23 and 25-31.
Depth 24 was more obviously broken and its support is ifdefed out. In
the other ranges, only depth 15 is common. It was broken by buffer
overruns in all cases.
bitmap.c:
- the static buffer was used even when it was too small (but it was
large enough to often work accidentally in depth 16)
- the size of the dynamically allocated buffer was too small
- the sizing info bitmap->PixelBytes was not inititialzed in the bitmap
constructor. It often ended up as 0 for MEMBUFs, so using it in more
places gave more null pointer accesses. (It is per-bitmap, but since
conversion between bitmaps of different depths is not supported (except
from 4 bits by padding to 8), it would work better if it were global.)
main.c:
- depths were rounded down instead of up to a multiple of 8, so PixelBytes
was 1 too small for depths above 8 except 16, 24 and 32.
- PixelBytes was not initialized for 4-bit planar modes. It isn't really
used for frame buffer accesses in these modes, but needs to be 1 in
MEMBUF images.
mouse.c:
- the mouse cursor buffers were too small.
vgl.h:
- PixelBytes was not initialized in the static bitmap constructor. It
should be initialized to the value for the current mode, but that is
impossible in a static constructor. Initialize it to -1 so as to
fail if it is used without further initialization.
All modes that are supposed to be supported now don't crash in
nontrivial tests, and almost work. Missing uses of PixelBytes now
give in-bounds wrong pointers instead of overruns. Misconversions of
bitmaps give multiple miscolored mouse cursors instead of 1 white one,
and similarly for bitmaps copied through a MEMBUF.
args (neither MAP_PRIVATE nor MAP_SHARED). It was broken in r271635
and/or r271724 by stricter checking. The compatibility code in r271724
doesn't work for my old binaries (actually new binaries with old
libraries).
PR: needed to test the fix for PR 162373
r343532 noted the difference between "hw.realmem" and "hw.physmem", which I
was previously unaware of. I discovered that neither sysctl had a
description visible via `sysctl -d', so I found where they were defined and
added suitable descriptions. While in the file, I went ahead and added
descriptions for all the others which lacked them. I also updated sysctl.3
accordingly
Reviewed by: kib, bcr
MFC after: 1 weeks
Sponsored by: Panasas
Differential Revision: https://reviews.freebsd.org/D19007
This commit backports revisions 00938b2b228f3b70d3d9e51f29a1505bdad43f1e and
59f90a338bce2376b540ee239cf4e269bf6d68ad from googletest's master branch to
our included version of googletest, which is based on 1.8.1. It adds the
GTEST_SKIP feature, which is very useful for a project like FreeBSD where
some tests depend on particular system configurations.
Reviewed by: ngie
Obtained from: github.com/google/googletest
MFC after: 2 months
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/rS345331
This makes it more consistent with other filesystems, which all end in "fs",
and more consistent with its mount helper, which is already named
"mount_fusefs".
Reviewed by: cem, rgrimes
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D19649
[ELF] Support --{,no-}allow-shlib-undefined
Summary:
In ld.bfd/gold, --no-allow-shlib-undefined is the default when
linking an executable. This patch implements a check to error on
undefined symbols in a shared object, if all of its DT_NEEDED entries
are seen.
Our approach resembles the one used in gold, achieves a good balance
to be useful but not too smart (ld.bfd traces all DSOs and emulates
the behavior of a dynamic linker to catch more cases).
The error is issued based on the symbol table, different from
undefined reference errors issued for relocations. It is most
effective when there are DSOs that were not linked with -z defs (e.g.
when static sanitizers runtime is used).
gold has a comment that some system libraries on GNU/Linux may have
spurious undefined references and thus system libraries should be
excluded (https://sourceware.org/bugzilla/show_bug.cgi?id=6811). The
story may have changed now but we make --allow-shlib-undefined the
default for now. Its interaction with -shared can be discussed in the
future.
Reviewers: ruiu, grimar, pcc, espindola
Reviewed By: ruiu
Subscribers: joerg, emaste, arichardson, llvm-commits
Differential Revision: https://reviews.llvm.org/D57385
Pull in r352943 from upstream lld trunk (by Fangrui Song):
[ELF] Default to --no-allow-shlib-undefined for executables
Summary:
This follows the ld.bfd/gold behavior.
The error check is useful as it captures a common type of ld.so
undefined symbol errors as link-time errors:
// a.cc => a.so (not linked with -z defs)
void f(); // f is undefined
void g() { f(); }
// b.cc => executable with a DT_NEEDED entry on a.so
void g();
int main() { g(); }
// ld.so errors when g() is executed (lazy binding) or when the program is started (-z now)
// symbol lookup error: ... undefined symbol: f
Reviewers: ruiu, grimar, pcc, espindola
Reviewed By: ruiu
Subscribers: llvm-commits, emaste, arichardson
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D57569
Together, these add support for --no-allow-shlib-undefined, and make it
the default for executables, so they will fail to link if any symbols
from needed shared libraries are undefined.
Reported by: jbeich
PR: 236062, 236141
MFC after: 1 month
X-MFC-With: r344779
