I'm getting into CMake and have some trouble with the syntax of it. I was wondering if any of you could tell me what the following command does exactly:
OPTION(USE_OPENGL "Use OpenGL" FOUND_OPENGL)
As far as I can tell, it will Default OPENGL to ON if it is found. Is that correct?
This command provides an option to the user to change a specific aspect of your build system. The syntax is explained in the documentation:
option(<option_variable> "help string describing option"
[initial value])
In your specific case, it will create an option called USE_OPENGL which should have the default value from the FOUND_OPENGL variable. So the default will probably be the same as the result of an automatic check whether opengl is available. However, the syntax is actually wrong in the example you give. It should be:
OPTION(USE_OPENGL "Use OpenGL" ${FOUND_OPENGL})
Options are specifically available through the ccmake command or the cmake gui. Here, the given documentation string will be available to the user. After the user has decided on the option, you can use the the variable given as the first argument like any other boolean variable in CMake. E.g.:
IF(USE_OPENGL)
MESSAGE(STATUS "Will us OpenGL")
ENDIF()
Related
My knowledge of Make is small. I have been told that everything you put after make (that does not contain "-") is a target.
Well a building process I have is failing.
First there is a line
make path/to/configuration_file
configuration_file is not a target. It is a autogenerated configuration file buried inside the directory structure ("path/to") that is of the form
#
# Boot Configuration
#
#
# DRAM Component
#
CONFIG_DRAM_TYPE_LPDDR4=y
# CONFIG_DRAM_TYPE_DDR4 is not set
CONFIG_DDR_SIZE=0x80000000
#
# Boot Device
#
# CONFIG_ENABLE_EMMC_BOOT is not set
# CONFIG_ENABLE_NAND_BOOT is not set
CONFIG_ENABLE_SPINAND_BOOT=y
# CONFIG_ENABLE_SPINOR_BOOT is not set
CONFIG_EMMC_ACCESS_8BIT=y
# CONFIG_EMMC_ACCESS_4BIT is not set
# CONFIG_EMMC_ACCESS_1BIT is not set
so I cannot understand how this is a target. For reference, when I run make there is a Makefile but this Makefile does not reference this file.
Still this line is going well.
The path where it fails says
make diags
and I have verified there is no "diags" target.
I will print here the error file that can give us more info of what is happening
GEN cortex_a/output/Makefile
Init diag test "orc_scheduler" ...
remoteconfig: Failed to generate configure in cortex_a/soc/visio/tests/orc_scheduler!
Makefile:11 recipe for target 'orc_scheduler-init' failed
make[10]: *** [orc_scheduler-init] Error 25
At least what I would like to know is how to interpret this error message. I don't know what the "11" or the "10" or the "25" refers to.
make is fundamentally a tool for automatically running commands in the right order so you don't have to type them in yourself. So all the commands make runs are commands that you could just type into your shell prompt. And all the errors that those commands generate are the same ones that you would see if you typed the command yourself. So, looking at make to try to understand those errors is looking in the wrong place: you have to look at the documentation for whatever command was invoked.
A "target" is just a file that make knows how to build. The fact that when you typed make <somefile> is didn't give you an error that it doesn't know how to build <somefile>, means that <somefile> is a target as far as your makefiles are concerned.
The error message Makefile:11: simply refers to the filename Makefile, line 11, which is where the command that make ran, that failed, can be found. But this likely won't help you solve the problem of why the command failed (unless the problem is you invoked it with the wrong arguments and you need to adjust the makefile to specify different arguments).
The command that failed generated the message:
remoteconfig: Failed to generate configure in cortex_a/soc/visio/tests/orc_scheduler!
I don't know what that means, but it's not related to make. You'll need to find out what this remoteconfig command is, what it does, and why it failed. It's unfortunate that it doesn't show any better error message as to why it failed to "generate configure", but again there's nothing make can do about that.
If you want to learn more about make you can look at the GNU make manual (note, GNU make is only one implementation of make; there are others and they are fundamentally the same but different in details).
It was my understanding that grub supports a small subset of bash. Their documentation doesn't go into super detail, other than it "supports conditionals", etc.
I am trying to run a simple if.
grub> if [ "${myvar}" = "fred" ]; then
> echo "test"
> fi
error: can't find command `['.
Anybody have an idea? I am using grub2-efi 2.00.
You are missing a grub2 module in order to run if tests.
I'm running Gentoo on a PowerPC system (PPC64 G5 machine) and doing a default grub-mkconfig then booting from it gives me the error in your question.
Since bash has that syntax support, I figured it was simply a grub module that needed to be added (I had been doing work with grub modules recently).
tl;dr: You need to load the appropriate grub module and then the error goes away.
The first step is to find out what modules you have. For me, it's whatever is available in my /boot/grub/powerpc-ieee1275/ folder.
There's also modules in /usr/lib/grub/powerpc-ieee1275/.
I wrote up a list of modules I thought I needed:
normal
eval
read
test
test_blockarg
trig
true
I then added them to my /etc/default/grub file:
GRUB_PRELOAD_MODULES="normal eval read test test_blockarg trig true"
I did not find an entry for GRUB_PRELOAD_MODULES in the config file, so I had to do some searching to find out how. I want these modules to be added every time I generate the grub config file, which means putting them in the 00_header portion of grub.
Then I recreated the configuration file:
grub-mkconfig -o /boot/grub/grub.cfg
The modules were in the header and things worked perfectly on reboot.
If I had to guess: you probably only need the test module to enable if statements.
Using ModelSim and VUnit I try to compile some UVVM, but this gives some warnings like:
** Warning: C:\work\Qtec\SVN_sim\Design\uvvm\uvvm_util\src\methods_pkg.vhd(1159): (vcom-1346) Default expression of interface object is not globally static.
So I would like to suppress these warnings, so I tried updating the VUnit "run.py" file with add_compile_option based on VUnit Python Interface:
uvvm_util = prj.add_library('uvvm_util')
uvvm_util.add_source_files(join(root, '../../uvvm/uvvm_util/src/*.vhd'))
uvvm_util.add_compile_option('modelsim.vcom_flags', ['-suppress 1346'])
But when compiling, I then get the error:
Compiling ....\uvvm\uvvm_util\src\types_pkg.vhd into uvvm_util ...
** Error (suppressible): (vcom-1902) Option "-suppress 1346" is either unknown, requires an argument, or was given with a bad argument.
You could edit the suppress entry in the modelsim.ini file. source
It could be a python/TCL error with spaces. See this link.
So the space between -suppress and 1346 is not properly forwarded.
The VUnit ui.py shows
modelsim.vcom_flags
Extra arguments passed to ModelSim vcom command.
Must be a list of strings.
I cannot test it, but this case the line should possibly be:
uvvm_util.add_compile_option('modelsim.vcom_flags', ['-suppress', '1346'])
edit: after some reading... To me the difference between add_compile_option and set_compile_option is not clear. Maybe you could try the other?
How do you pass options to stack haddock from stack.yaml? I cannot find any clue to correct syntax neither in documentation nor in stack source code.
Documentation describes the following:
build:
haddock-arguments: ""
Naive haddock-arguments: "--odir=./docs" fails with type error:
…failed to parse field 'haddock-arguments': expected HaddockOptsMonoid, encountered String
I figured out that it expects it to be like:
build:
haddock-arguments:
odir: "./docs"
However it fails with error Unrecognized field in HaddockOptsMonoid: odir.
What is correct syntax of passing arguments from haddock manual to stack via stack.yaml? In my specific case, I want specify custom output directory.
After looking at the source I figured out that the syntax is
build:
haddock-arguments:
haddock-args:
- "--odir=./docs"
In a sample project this has the following result (notice the location of the docs directory deep down in .stack-work):
$ ls .stack-work/install/x86_64-linux/lts-6.3/7.10.3/doc/docs/ | cat
doc-index.html
frames.html
haddock-util.js
hslogo-16.png
index-frames.html
index.html
minus.gif
ocean.css
plus.gif
synopsis.png
The links in index.html are broken, so I'm slightly pessimistic that you can achieve what you want by passing arguments to haddock in this way.
As part of a little project, I'm writing a shell in Ada. As such, when I was investigating the system calls, I learned that there are three ways to do it.
The POSIX system calls, which are probably the least reliable.
Passing the arguments along to C's system(), which I didn't really want to do, since this was about writing the emulator in Ada and not C.
Using GNAT's runtime libraries.
I chose to go for the last option, considering this to be the most "Ada-like" of the choices. I found a code snippet on RosettaCode here. I copied and pasted it and compiled it after changing the "cmd.exe" to "ls" and removing the second argument definition. However, nothing happens when I run the executable. The shell just goes right back to the prompt. I have tested this on two different computers, one running Fedora 21, the other Debian Jessie. Here's what I've done to test it:
Seen if lacking an arguments string caused it
Checked if any of the file descriptors in GNAT's libraries are mis-named
Redirected both stderr and stdin to stdout just to see if GNAT was dumping them to the wrong FD anyway.
Looked thoroughly through the System.OS_lib library file, and there seems to be no reason.
Googled it, but GNAT's own page on the GCC website is very poorly documented.
For now I'm using the C.Interface system in the preparation of my shell, but I'm dissatisfied with this. I'm new to Ada and have only been tinkering with it for a month or so now, so if there's some kind of Ada wisdom here that would help I'm not in on it.
UPDATE: I have tried running it with absolute path, both to /usr/bin and /bin locations, and it doesn't work. Interestingly, the result code returned by the operating system is 1, but I don't know what that means. A quick search suggests that it's for "all general errors", and another site suggests that it's for "incorrect functions".
I had to tweak the RosettaCode example a little to run /bin/ls on Debian Linux, but it does run as expected...
with Ada.Text_IO; use Ada.Text_IO;
with Gnat.OS_Lib; use Gnat.OS_Lib;
procedure Execute_Synchronously is
Result : Integer;
Arguments : Argument_List :=
( 1=> new String'("-al")
);
begin
Spawn
( Program_Name => "/bin/ls",
Args => Arguments,
Output_File_Descriptor => Standout,
Return_Code => Result
);
for Index in Arguments'Range loop
Free (Arguments (Index));
end loop;
end Execute_Synchronously;
Changes :
my Gnat (FSF Gnat 4.92 from Debian Jessie) warned about System.OS_Lib, recommending Gnat.OS_Lib instead. (Which simply renames System.OS_Lib .... why???
System.OS_Lib comments:
-- Note: this package is in the System hierarchy so that it can be directly
-- be used by other predefined packages. User access to this package is via
-- a renaming of this package in GNAT.OS_Lib (file g-os_lib.ads).
Program name including path.
Arguments. The first time I ran it, it displayed the details of "ls" itself, because it was given its own name as the first argument, so I deleted that to see the current directory instead.
Notes :
the best information ot the available subprograms and their arguments is usually in the package specs themselves in the "adainclude" folder : this is /usr/lib/gcc/x86_64-linux-gnu/4.9/adainclude on my Debian installation, locate system.ads will find yours. The specific files are: s-os_lib.ads for System.OS_Lib which exports Spawn and Standout, and a-textio.ads for Ada.Text_IO.
Standout is not the preferred way of accessing Standard Output : it's a file descriptor (integer), the preferred way would be the Standard_Output function from Ada.Text_IO which returns a File. However there doesn't seem to be an overload for Spawn which takes a File (nor would I expect one in this low level library) so the lower level file descriptor is used here.
Absent a shell, you'll need to search the PATH yourself or specify a full path for the desired executable:
Spawn (
Program_Name => "/bin/ls",
…
);
I have tried running it with absolute path…neither /usr/bin nor /bin locations work.
Use which to determine the full path to the executable:
$ which ls
/bin/ls