Can't build a Skia module (SkPlainTextEditor) - build

I'm trying to build Skia's modules/skplaintexteditor:
https://chromium.googlesource.com/skia/+/master/modules/skplaintexteditor/
I have followed the instructions in README.md:
tools/git-sync-deps
bin/gn gen out/default
ninja -C out/default editor
The first two commands are working, but the ninja build is failing with:
ninja: error: unknown target 'editor'
Skia itself is building fine (i.e. if I don't specify the editor target in the ninja command).
What is missing here? How do I build skplaintexteditor?

Brian Osman answered in this topic on Google Groups:
Currently, all of our "test" tools (which includes experimental modules like the editor) fall under the skia_enable_tools umbrella. That requires gpu support (skia_enable_gpu = true), and static linking (is_component_build = false). The logic to enforce this is at the end of gn/skia.gni. Some of the experimental modules used by the editor use private Skia APIs, so those modules don't handle component builds correctly.
So, adding the arguments:
is_component_build = false
skia_enable_gpu = true
fixes the build.

Related

Provide run time environment variable path (e.g. LD_LIBRARY_PATH) to third party dependency in bazel

In the code base I am working with we use the oracle instant client library as a third party dependency in Bazel as follows:
cc_library(
name = "instant_client_basiclite",
srcs = glob(["*.so*"]),
visibility = ["//visibility:public"],
)
The library looks as this:
$ bazel query 'deps(#instant_client_basiclite//:instant_client_basiclite)'
#instant_client_basiclite//:instant_client_basiclite
#instant_client_basiclite//:liboramysql.so
#instant_client_basiclite//:libociicus.so
#instant_client_basiclite//:libocci.so.21.1
#instant_client_basiclite//:libocci.so
#instant_client_basiclite//:libnnz21.so
#instant_client_basiclite//:libclntshcore.so
...
It works as far as linking is concerned, but it seems that the path to the library is still needed because otherwise I get a run time error (oracle error 1804). The error can be solved by setting any of the environment variables ORACLE_HOME or LD_LIBRARY_PATH. In fact for the IBM WebSphere MQ there is the same need (character encoding table files need to be found).
ldd on a binary points to .../bazel-bin/app/../../../_solib_k8/_U#instant_Uclient_Ubasiclite_S_S_Cinstant_Uclient_Ubasiclite___U/libocci.so.21.1
How can I set those needed path variables so that bazel test, bazel run and Bazel container image rules work?
One possibility is to add the following command line option:
--test_env=ORACLE_HOME="$(bazel info output_base)/external/instant_client_basiclite"
It is a pity that it cannot be put in .bazelrc.

Package build ignores Makevars flags

Question
I'm trying to tell my package to use gcc to compile the C++ code in stead of clang. Why aren't my CXX flags in my Makevars file being used?
(I am expecting/hoping the solution to be something really simple that I've overlooked.)
It's my understanding (see references) that I can specify CXX* flags in either
src/Makevars in the package, or
~/.R/Makevars
However, I can't get option 1 to work, only option 2.
Example Builds
Here are screenshots showing the build options I'm using. In each case I'm showing both the Makevars and the /.R/Makevars files to show which one I'm using in each case.
Option 1: src/Makevars
Here I specify CXX11 = /usr/local/bin/g++-7 inside src/Makevars. The build messages say it's building with clang
Option 2: ~/.R/Makevars
Here I specify CXX11 = /usr/local/bin/g++-7 inside ~/.R/Makevars. The build message shows it builds with g++
Example package
I've noticed this on a few packages I've built recently using Rcpp, but if you want an example to test my googlePolylines package is here on github.
References
Building R packages using Alternate GCC
Understanding the contents of Makevars
Session Info
devtools::session_info()
Session info ----------------------------------------------------------------------------------------------
setting value
version R version 3.4.3 (2017-11-30)
system x86_64, darwin15.6.0 ## Mac OS
ui RStudio (1.1.414)
language (EN)
collate en_AU.UTF-8
tz Australia/Melbourne
date 2018-03-11
Quoting Duncan Murdoch in https://stat.ethz.ch/pipermail/r-package-devel/2017q4/002087.html:
According to section 1.2.1 "Using Makevars" in Writing R Extensions,
R_HOME/etcR_ARCH/Makeconf is included after Makevars, so what you're
seeing is by design. I believe this is so that packages are built with
tools compatible with those that built R. (Remember, packages are
designed for distribution to diverse systems.)
So you might change various flags within src/Makevars via for example PKG_CXXFLAGS, but you cannot overwrite CXXFLAGS or CXX itself. And there is no PKG_CXX.

Compiling Tensorflow with a custom Clang + Libc++ (instead of stdlibc++)

I am trying to compile tensorflow with a custom clang/llvm toolchain and using clang's native libc++ (instead of borrowing Gcc's stdlibc++).
It looks like bazel plain assumes that every clang will use Gcc's libraries because I get these errors:
$ bazel build --cxxopt=-std=c++11 --cxxopt=-stdlib=libc++ tensorflow:libtensorflow.so
INFO: Found 1 target...
INFO: From Compiling
external/protobuf/src/google/protobuf/compiler/js/embed.cc [for host]:
external/protobuf/src/google/protobuf/compiler/js/embed.cc:37:12:
warning: unused variable 'output_file' [-Wunused-const-variable]
const char output_file[] = "well_known_types_embed.cc";
^
1 warning generated.
ERROR: /home/hbucher/.cache/bazel/_bazel_hbucher/ad427c7fddd5b68de5e1cfaa7cd8c8cc/external/com_googlesource_code_re2/BUILD:11:1: undeclared inclusion(s) in rule '#com_googlesource_code_re2//:re2':
this rule is missing dependency declarations for the following files included by 'external/com_googlesource_code_re2/re2/bitstate.cc':
'/home/hbucher/install/include/c++/v1/stddef.h'
'/home/hbucher/install/include/c++/v1/__config'
I tried to hack into tools/cpp/CROSSTOOL inside bazel as some posts suggested to add the line
cxx_builtin_include_directory: "/home/hbucher/install/include/c++/v1"
but to no avail, it does not seem to make any difference.
Then I tried to follow a bazel tutorial to create a custom toolchain. The text does not help much because they are actually writing a cross tool while what I am trying to do is to tweak the existing host rules and somehow bazel seems to undo every attempt I try to tweak its parameters.
I have got to the point that is currently in my github repository https://github.com/HFTrader/BazelCustomToolchain
However it does not compile and I cannot even figure out how to start debugging this message.
$ bazel build --crosstool_top=#hbclang//:toolchain tensorflow:libtensorflow.so
.....................
ERROR: The crosstool_top you specified was resolved to
'#hbclang//:toolchain', which does not contain a CROSSTOOL file. You can
use a crosstool from the depot by specifying its label.
INFO: Elapsed time: 2.216s
I have appended these lines to my tensorflow/WORKSPACE
new_local_repository(
name="hbclang",
path="/home/hbucher/BazelCustomToolchain",
build_file = "/home/hbucher/BazelCustomToolchain/BUILD",
)
I have asked this question on bazel's google groups but they redirected me to stackoverflow. At this point I am about to give up.
Have someone attempted to do this or I'm breaking ground here?
Thank you.
Solved. Not in the intended way but it works for me.
export INSTALL_DIR="$HOME/install"
export CC=$INSTALL_DIR/bin/clang
export CXX=$INSTALL_DIR/bin/clang++
export CXXFLAGS="-stdlib=libc++ -L$INSTALL_DIR/lib"
export LDFLAGS="-L$INSTALL_DIR/lib -lm -lrt"
export LD_LIBRARY_PATH="/usr/lib:/lib/x86_64-linux-gnu/:$INSTALL_DIR/lib"
git clone https://github.com/tensorflow/tensorflow.git tensorflow-github
cd tensorflow-github
mkdir build-tmp && cd build-tmp
cmake ../tensorflow/contrib/cmake/
make -j4
Easy as 1-2-3 with cmake
[2020-05-24: Edit to make the answer up to date.]
TLDR: To build a project with Bazel with a specific Clang binary, and with libc++, this works for me (where INSTALL_DIR is where I've installed llvm):
CC="$INSTALL_DIR/bin/clang" \
BAZEL_CXXOPTS="-stdlib=libc++:-isystem$INSTALL_DIR/include" \
BAZEL_LINKOPTS="-stdlib=libc++" \
BAZEL_LINKLIBS="-L$INSTALL_DIR/lib:-Wl,-rpath,$INSTALL_DIR/lib:-lc++:-lm" \
bazel test //...
Background:
You can use --repo_env option, e.g. --repo_env=CC=clang, to put these defaults into your project- or system-wide .bazelrc.
This approach uses Bazel's C++ toolchain autoconfiguration which doesn't attempt to declare all the toolchain inputs in BUILD files. This is to simplify the configuration for the user. Therefore whenever you modify the C++ toolchain in a way that Bazel cannot know about (rebuild llvm etc.), you have to run bazel clean --expunge to flush the cache and rerun the autoconfiguration the next time.
The robust solution to specifying C++ toolchain in Bazel is to use the CcToolchainConfigInfo. See the documentation at https://docs.bazel.build/versions/master/tutorial/cc-toolchain-config.html and https://docs.bazel.build/versions/master/cc-toolchain-config-reference.html.

How can I use Google Test with my project that builds via autotools?

It seems like there are a few answers that kind-of, sort-of make sense, but that I don't know how to carry out. And I haven't found a comprehensive answer.
The First Problem
Google Test should not be an installed library, it should be built with the project. (See the FAQ.) As far as I can tell, this means the Google Test libraries are a dependency of my unit tests, and should be built when I run "make check" within my project for the first time. This should build Google Test libraries in some directory. I don't know how to do this. It mentions some autotools script that's deprecated, and I'm not sure what they're talking about or how to point my build at it properly.
The Second Problem
Assuming the build is successful, how do I write a test that uses my locally-compiled version of Google Test to run tests? I assume that there are a bunch of Makefile.am commands I put in my tests directory. But what are they? And what's an example of a unit test that uses Google Test?
I have solved the problem to my satisfaction! I will move on entirely now. This is basically asking for a tutorial. There are a lot of decisions that must be made, hopefully logically, so that Google Test dovetails nicely into autotools. So I apologize in advance for the long answer, but all the details should be there.
The First Problem
In order to understand the answer, the question needs to be rephrased a little. We are compiling Google Test as a library which our test code will link to. The library will not be installed. The question we want to ask is
"How do we configure autotools to compile Google Test as a library
which our test code can link against?"
In order to do that, we need to download Google Test and place it into our project. I use Github, so I do that by adding a submodule in the root path of my project:
$ git submodule add git#github.com:google/googletest.git
$ git submodule init
$ git submodule update
This downloads googletest into my root of my project:
/:
Makefile.am
configure.ac
src/:
(files for my project)
tests/:
(test files)
googletest/:
googletest/:
include/:
(headers, etc., to be included)
gtest/:
gtest.h
m4/:
(directory for m4 scripts and things)
src/:
(source files for Google Test)
I need to compile per the instructions. I only want the Google Test library to be built upon running make check, so I will use check_LTLIBRARIES. I add the following to my tests Makefile.am in /tests:
check_LTLIBRARIES = libgtest.la
libgtest_la_SOURCES = ../googletest/googletest/src/gtest-all.cc
libgtest_la_CPPFLAGS = -I$(top_srcdir)/googletest/googletest/include -I$(top_srcdir)/googletest/googletest
libgtest_la_LDFLAGS = -pthread
This requires subdir-objects to be enabled in configure.ac. That is accomplished by adding it to the AM_INIT_AUTOMAKE line. I also need to include the makefile in AC_CONFIG_FILES. We also want to use libtool, because we are compiling library files (I'll explain why and how that works in a moment). To use libtool, we add AM_PROG_AR, LT_INIT. We want autoreconf to install m4 macros to /m4, and then we want automake to find them, so we need AC_CONFIG_MACRO_DIRS. My configure.ac has lines updated:
AM_INIT_AUTOMAKE([-Wall -Werror subdir-objects])
...
AM_PROG_AR
LT_INIT
AC_CONFIG_MACRO_DIRS([m4])
...
AC_CONFIG_FILES([Makefile
src/Makefile
tests/Makefile
])
I also need to include the subdirectory and a line pointing to the macros in the /m4 macros directory in my /Makefile.am:
ACLOCAL_AMFLAGS = -I m4
SUBDIRS = src tests
What has this done? Libtool has been enabled with AM_PROG_AR and LT_INIT. The check_LTLIBRARIES means we will use libtool to create what's called a convenience library called libgtest.la. With subdir-objects enabled, it will be built into the /tests directory, but not installed. This means that, whenever we want to update our tests, we don't have to recompile the Google Test library libgtest.la. This will save time when testing and help us iterate faster. Then, we will want to compile our unit tests against it later as we update them. The library will only be compiled upon running make check, saving time by not compiling it if all we want to do is make or make install.
The Second Problem
Now, the second problem needs to be refined: How do you (a) create a test (b) that is linked to the Google Test libraries and thus uses them? The questions are kind of intertwined, so we answer them at once.
Creating a test is just a matter of putting the following code into a gtest.cpp file located at /tests/gtest.cpp:
#include "gtest/gtest.h" // we will add the path to C preprocessor later
TEST(CategoryTest, SpecificTest)
{
ASSERT_EQ(0, 0);
}
int main(int argc, char **argv)
{
::testing::InitGoogleTest(&argc, argv);
return RUN_ALL_TESTS();
}
This runs only the simple test 0=0. To create a test for your library, you need to read the primer. You'll notice we don't need a header for this (yet). We are linking to the file "gtest/gtest.h", so we'll need to make sure that we tell automake to include a directory that has gtest/gtest.h.
Next, we need to tell automake that we want to build a test and run it. The test is going to build into an executable that we don't want to install. Then automake is going to run that executable. It will report whether that executable says the tests passed or failed.
Automake does that by looking in the makefile for the variable check_PROGRAMS. These are the programs it will compile, but it won't necessarily run them. So we add to /tests/Makefile.am:
check_PROGRAMS = gtest
gtest_SOURCES = gtest.cpp
gtest_LDADD = libgtest.la
gtest_LDFLAGS = -pthread
gtest_CPPFLAGS = -I$(top_srcdir)/googletest/googletest/include -I$(top_srcdir)/googletest/googletest -pthread
The gtest_SOURCES finds the /tests/gtest.cpp file and compiles it. gtest_LDADD links against libgtest.la which will be compiled into the /tests directory. Google wants us to use the gtest_LDFLAGS line to enable pthreads. Finally, we need to include the location where the header "gtest/gtest.h" will be found, and that is the gtest_CPPFLAGS line. Google also wants us to include the /googletest/googletest location, and include the
The state of things: The Google Test library libgtest.la will compile with make into the directory /tests, but not be installed. The binary gtest will only be compiled with make check, but will not be installed.
Next we want to tell automake to actually run the compiled binary gtest and report errors. This is accomplished by adding a line to /tests/Makefile.am:
TESTS = gtest
The final /tests/Makefile.am looks like this:
check_LTLIBRARIES = libgtest.la
libgtest_la_SOURCES = ../googletest/googletest/src/gtest-all.cc
libgtest_la_CPPFLAGS = -I$(top_srcdir)/googletest/googletest/include -I$(top_srcdir)/googletest/googletest -pthread
check_PROGRAMS = gtest demo
gtest_SOURCES = gtest.cpp ../src/fields.cpp
gtest_LDADD = libgtest.la
gtest_LDFLAGS = -pthread
gtest_CPPFLAGS = -I$(top_srcdir)/googletest/googletest/include -I$(top_srcdir)/src
demo_SOURCES = demo.cpp ../src/fields.cpp
demo_CPPFLAGS = -I$(top_srcdir)/src
TESTS = gtest
Now, autoreconf -fiv (note any errors and hopefully fix them) from /, and make check and you should get a test that runs:
build(dev)$ make check
Making check in tests
/Applications/Xcode.app/Contents/Developer/usr/bin/make gtest
make[2]: `gtest' is up to date.
/Applications/Xcode.app/Contents/Developer/usr/bin/make check-TESTS
PASS: gtest
============================================================================
Testsuite summary for IonMotion 0.0.1
============================================================================
# TOTAL: 1
# PASS: 1
# SKIP: 0
# XFAIL: 0
# FAIL: 0
# XPASS: 0
# ERROR: 0
============================================================================
Here is a sample Makefile.am for the unit test project (project name: TestProject). It depends on GTEST and GMOCK:
Makefile.am
#######################################
# The list of executables we are building seperated by spaces
# the 'bin_' indicates that these build products will be installed
# in the $(bindir) directory. For example /usr/bin
#bin_PROGRAMS=exampleProgram
# Because a.out is only a sample program we don't want it to be installed.
# The 'noinst_' prefix indicates that the following targets are not to be
# installed.
noinst_PROGRAMS=utTestProject
#######################################
# Build information for each executable. The variable name is derived
# by use the name of the executable with each non alpha-numeric character is
# replaced by '_'. So a.out becomes a_out and the appropriate suffex added.
# '_SOURCES' for example.
# Sources for the a.out
utTestProject_SOURCES= \
utTestProject.cpp
# Library dependencies
utTestProject_LDADD = \
$(top_srcdir)/../TestProject/build/${host}/libTestProject/.libs/libTestProject.a \
../$(PATH_TO_GTEST)/lib/libgtest.a \
../$(PATH_TO_GMOCK)/lib/libgmock.a
# Compiler options for a.out
utTestProject_CPPFLAGS = \
-std=c++11 \
-I../$(PATH_TO_GTEST)/include \
-I../$(PATH_TO_GMOCK)/include \
-I$(top_srcdir)/include \
-I$(top_srcdir)/..
TESTS = utTestProject
TESTS_ENVIRONMENT = export UT_FOLDER_PATH=$(top_srcdir)/utTestProject; \
export GTEST_OUTPUT="xml";
Compiling gtest:
# Useful vars
SourceVersionedArchiveFolderName="gtest-1.7.0"
#
# Make it
#
pushd .
cd ./${SourceVersionedArchiveFolderName}/make
make gtest.a
if [ $? != 0 ]; then
echo "$0: Make failed"
exit 1
fi
popd
It's worth noting that Googletest doesn't officially maintain its Autotools integration anymore:
Before settling on CMake, we have been providing hand-maintained build
projects/scripts for Visual Studio, Xcode, and Autotools. While we
continue to provide them for convenience, they are not actively
maintained any more. We highly recommend that you follow the
instructions in the above sections to integrate Google Test with your
existing build system.
https://github.com/google/googletest/tree/master/googletest#legacy-build-scripts
It's now recommended to build Googletest with CMake.
Making GoogleTest's source code available to the main build can be
done a few different ways:
Download the GoogleTest source code manually and place it at a known
location. This is the least flexible approach and can make it more
difficult to use with continuous integration systems, etc.
Embed the
GoogleTest source code as a direct copy in the main project's source
tree. This is often the simplest approach, but is also the hardest to
keep up to date. Some organizations may not permit this method.
Add
GoogleTest as a git submodule or equivalent. This may not always be
possible or appropriate. Git submodules, for example, have their own
set of advantages and drawbacks.
Use CMake to download GoogleTest as
part of the build's configure step. This is just a little more
complex, but doesn't have the limitations of the other methods.
https://github.com/google/googletest/tree/master/googletest#incorporating-into-an-existing-cmake-project

How to add depdency in waf builder's wscript script

In my project (which uses waf/wscript based build system), I am now adding mongodb c++ driver APIs. I figured out that 'libmongoclient.a' is not getting added as a linker option (at compile time) and I get all undefined reference to the mongodb c++ driver API calls.
I want to understand, how do I modify my wscript so that it picks up the mongoclient related library by itself and links it properly. It perhaps involves updating the configuration function of wscript. I am new to the waf build system, and not sure how to change it.
I have built and installed the mongodb c++ driver as follows:
- INCLUDE: /usr/local/include/mongo/
- LIB: /usr/local/lib/libmongoclient.a
I posted a similar question earlier in this regard, and the above one is more specific problem statement.
https://stackoverflow.com/questions/30020574/building-project-with-waf-script-and-eclipse
Since I am just invoking ./waf from within eclipse, I believe, the options that I specify into Eclipse's build environment are not being picked up by the waf (and hence the library option for mongoclient).
I figured this out and the steps are as follows:
Added following check in the configure command/function.
conf.check_cfg(package='libmongoclient', args=['--cflags', '--libs'],
uselib_store='MONGOCLIENT', mandatory=True)
After this step, we need to add a package configuration file (.pc) into /usr/local/lib/pkgconfig path. This is the file where we specify the paths to lib and headers. Pasting the content of this file below.
prefix=/usr/local
libdir=/usr/local/lib
includedir=/usr/local/include/mongo
Name: libmongoclient
Description: Mongodb C++ driver
Version: 0.2
Libs: -L${libdir} -lmongoclient
Cflags: -I${includedir}
Added the above library into the build function to the sepcific program which depends on the above dependency (i.e. MongoClient).
mobility = bld(
target='bin/mobility',
features='cxx cxxprogram',
source='src/main.cpp',
use='mob-objects MONGOCLIENT',
)