Spec not allow body (remove in gpr file) without touching source files - ada

I got the following error wich is common with generated sources:
spec of this package does not allow a body
I would like to know if it exist a rule to put in the gpr file to ignore this error.
Like a ignore flag.
As I mentionned this files are generated so i have no right on them (not alowed to suppress them neither rewrite them).
More over it would be nice to have a rule that work for every generation.

If you were to compile
package Guillaume is
end Guillaume;
package body Guillaume is
end Guillaume;
in Ada 1983 mode, you would get e.g.
gnatmake -gnat83 guillaume.ads
gcc -c -gnat83 guillaume.ads
guillaume.ada:1:09: warning: package "Guillaume" does not require a body
guillaume.ada:1:09: warning: body in file "guillaume.adb" will be ignored
Having a body that isn’t required by the spec was made illegal with Ada 95 (it would be possible to change a body and for the compilation process not to notice that it needed to be recompiled, leading to confusion). If your code generator was designed to produce Ada 83, then I guess you may have to face compiling in Ada 83 mode - but GNAT doesn’t, as far as I know, guarantee to be 100% compatible, particularly as far as the run time system is concerned.
Are the offending package bodies all actually empty? If so, you might be able to list them and use the Excluded_Source_List_File attribute in your project. If not, you are in trouble, because there’s no way (without changing package sources) to get the code in them to execute.
(Later): actually, Excluded_Source_List_File doesn’t help; it stops gprbuild looking at the file, but not the compiler; and it’s the compiler that rejects the body. Sorry. But if you could make such a list you could use it to delete the bad bodies.

You can exclude the body from the list of source files:
for Excluded_Source_Files use ("my_body.adb");

Related

GNAT Metric and RTL files

For running GNAT metric (for Windows, GPL 2017 or CE 2018) I'd like to include the RTL sources as well. There is a "-a" switch but it seems to be ineffective. When I'm forcing visibility of RTL sources, only ada.ads and system.ads are processed. Guessing it is a "crunched name" issue (RTL file names forced to 8 character names) I've tried other tricks without success.
My question is: is there a way to get the RTL source metrics (of the source files actually used) with GNAT Metric?
I'm using the command
gnatmetric -a -xs -nt -j0 -Pmyproj.gpr -U somemain.adb
TIA
In the meantime I've found a workaround by using the gnathtml.pl script.
I've customized the script a bit by removing the H1 headers.
The result is a few hundreds of HTML files with the sources of units actually used: the script does find all dependencies, recursively, through the .ali files - including the RTL.
Then I group the HTML files together, convert them back to text files, pass them through Adalog's Normalize tool for removing comments and empty lines, count lines with the wc command, and the job is done.

Frama-C aborted Invalid user input

I am very new to Frama-c and I got an issue when I am trying to open a C source file.
The error shows as
"fatal error: event.h: No such file or directory. Compilation terminated".
[kernel] Parsing FRAMAC_SHARE/libc/__fc_builtin_for_normalization.i (no preprocessing)
[kernel] Parsing WorkSpace/bipbuffer.c (with preprocessing)
[kernel] user error: failed to run: gcc -E -C -I. -dD -D__FRAMAC__ -nostdinc -D__FC_MACHDEP_X86_32 -I/usr/share/frama-c/libc -o '/tmp/bipbuffer.ce6d077.i' '/home/xxx/WorkSpace/bipbuffer.c' you may set the CPP environment variable to select the proper preprocessor command or use the option "-cpp-command".
[kernel] user error: stopping on file "/home/xxx/WorkSpace/bipbuffer.c" that has errors. Add'-kernel-msg-key pp' for preprocessing command.
So bascially I am trying to open a C source file but it returns an error like this. I aslo tried other very simple C files like hello world and other slicing functions, it works well.
I thought it was because I didn't have the dependencies of 'event.h' but it still return these errors after I installed the libevent dependencies. I am not sure if I need to manually set some path of the dependencies for frama-c
Here is part of the C file (Source link: https://memcached.org/) that I would like to open:
#include "stdio.h"
#include <stdlib.h>
/* for memcpy */
#include <string.h>
#include "bipbuffer.h"
static size_t bipbuf_sizeof(const unsigned int size)
{
return sizeof(bipbuf_t) + size;
}
int bipbuf_unused(const bipbuf_t* me)
{
if (1 == me->b_inuse)
/* distance between region B and region A */
return me->a_start - me->b_end;
else
return me->size - me->a_end;
}
......
Thanks,
Compilers and other tools working with C source code need to know where to find header files. There are some standard places where they look automatically, but Frama-C has fewer of those than (and different ones from) a normal compiler.
You need to find out where event.h is installed, then pass something like -cpp-extra-args "-I /path/to/directory/" to Frama-C. Pass the directory name only, not including the name event.h itself.
In addition to Isabelle Newbie's answer, I'd like to point out that the Chlorine version of Frama-C, whose beta has been recently announced, features a new option -json-compilation-database that attempts to read the arguments to be passed to the pre-processor from a compilation database.
Such database can be generated directly by cmake, but there are solutions for make-based project such as the one you refer to, in particular bear, which intercepts the commands launched by make to build the database.
Here's a detailed summary of how you could proceed, using the new -json-compilation-database option from Frama-C 17 Chlorine, plus an extra script list_files.py (which is not in the beta, but will be available in the final 17 release, and can be downloaded here):
Get the source files you want to analyze with Frama-C, run ./configure, and if possible try to disable optional dependencies from external libraries; for instance, some code bases include optional dependencies based on availability of libraries/system features, but have fallback options (resorting to standard C library or POSIX functions). The more you give Frama-C, the better the chances of analyzing it well, so if such external libraries are not essential, excluding them might help get a more "POSIXy" code, which should help. This is typically visible in config.h files, in macros commonly named HAVE_*.
Compile and install Build EAR or some equivalent tool to obtain a compile_commands.json file.
Run bear make (or cmake with flag CMAKE_EXPORT_COMPILE_COMMANDS) to get the compile_commands.json file.
Run the aforementioned list_files.py in the directory containing compile_commands.json to obtain the list of C sources used during compilation.
Run Frama-C (17 Chlorine or newer), giving it the list of sources found in the previous step, plus option -json-compilation-database . to parse the compile_commands.json and, hopefully, get the appropriate preprocessing flags.
Ideally, this should suffice, but in practice, this is rarely enough. In particular due to the presence of external libraries and non-C99, non-POSIX functions, the following steps are always needed.
6. Inclusion of external libraries
At this step, Frama-C will complain about the lack of event.h. You'll have to include the headers of this library yourself. Note: copying headers directly from your /usr/include is not likely to work, due to several architecture-specific definitions, especially files such as bits/*.h..
Instead, consider downloading the external libraries and preparing them (e.g. running ./configure at least). Then manually add the extra include directory via -cpp-extra-args="-I <path/to/your/sources/for/libevent.h>/include".
7. Inclusion of missing non-POSIX headers
Some other headers may be missing, in particular GNU- or BSD-specific sources (e.g. sysexits.h). Get these headers and add them when necessary. The error message in this case comes from the preprocessor (gcc) and is similar to this:
memcached.c:51:10: fatal error: sysexits.h: No such file or directory
#include <sysexits.h>
^~~~~~~~~~~~
compilation terminated.
8. Definition of missing non-POSIX types and constants
At this point, all necessary headers should be available, but parsing with Frama-C may still fail. This is due to usage of non-POSIX type definitions (e.g. caddr_t, struct ling), non-POSIX constants (e.g. MAXPATHLEN, SOCK_NONBLOCK, NI_MAXSERV). Error messages typically resemble the following:
[kernel] memcached.c:3261: Failure: Cannot resolve variable MAXPATHLEN
Constants are often easy to provide manually, by grepping what's available in your /usr/include.
Type definitions, on the other hand, may require some copy-pasting at the right places, especially if they depend on other types which are also missing. This step is hardly automatizable, but relatively straightforward once you get used to some specific error messages.
For instance, the following error message is related to a missing type definition (caddr_t):
[kernel] Parsing memcached.c (with preprocessing)
[kernel] memcached.c:1074:
syntax error:
Location: line 1074, between columns 38 and 47, before or at token: c
1072 *hdr++ = 0;
1073 *hdr++ = 0;
1074 assert((void *) hdr == (caddr_t)c->msglist[i].msg_iov[0].iov_base + UDP_HEADER_SIZE);
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
1075 }
1076
Note that the token just before c is (caddr_t), which has never been defined (it is often defined as either void * or char *).
The following error message is related to an incomplete type, i.e., a struct used somewhere but never defined:
[kernel] memcached.c:5811: User Error:
variable `ling' has initializer but incomplete type
It means that variable ling's type, which is struct linger (non-POSIX), has never been defined. In this case, we can copy it from our /usr/include/bits/socket.h:
struct linger
{
int l_onoff; /* Nonzero to linger on close. */
int l_linger; /* Time to linger. */
};
Note: if there are POSIX constants/definitions missing from Frama-C's libc, consider notifying its developers, or proposing pull requests in Frama-C's Github.
9. Fixing incompatible and missing function prototypes
Parsing is likely to succeed after the previous step, but it may still fail due to incompatible function prototypes. For instance, you may get:
[kernel] User Error: Incompatible declaration for usleep:
different integer types int and unsigned int
First declaration was at assoc.c:238
Current declaration is at items.c:1573
This is the consequence of a warning emitted earlier:
[kernel:typing:implicit-function-declaration] slabs.c:1150: Warning:
Calling undeclared function usleep. Old style K&R code?
It means that function usleep is called, but it does not have a prototype, therefore Frama-C uses the pre-C99 convention of "implicit int": it generates such a prototype, but later in the code, an actual declaration of usleep is found, and its type is not int. Hence the error.
To prevent this, you need to ensure usleep's prototype is properly included. Since it is not POSIX.1-2008, you need to either define/undefine the appropriate macros (see unistd.h), or add your own prototype.
At the end, this should allow Frama-C to parse the files and build an AST.
However, there are several missing prototypes yet; we were just lucky that none conflicted with actual declarations. Ideally, you'll consider the parsing stage done when there are no more messages such as implicit-function-declaration and similar warnings.
Some of the missing prototypes in memcached, such as getsubopt, are POSIX and should be integrated into Frama-C's standard library. Others might make part of a small library of non-standard stubs, to be reused for other software.
Contributing with results for future reuse
Successful conclusion of the parsing stage for such open source libraries is enough to consider them for integration into this repository of open source case studies, so that future users can start their analyses without having to redo all of these steps. (The repository is oriented towards Eva, but not exclusively: parsing is useful for all of Frama-C plug-ins.)

make does not realize that a relative path name dependency is the same as an absolute pathname target

The following is a simplified makefile for a problem I'm having:
all: /tmp/makey/../filey
#echo All done
/tmp/filey:
#echo Filey
When I run make it says:
make-3.79.1-p7: * No rule to make target /tmp/makey/../filey', needed byall'. Stop.
Clearly it does not realize that /tmp/makey/../filey is the same as /tmp/filey. Any ideas how I can make this work?
Thanks
Ciao
-- Murali
Newer versions of GNU make have $(abspath ...) and $(realpath ...) functions you can apply to your prerequisites and targets to resolve the paths to the same string. If you've constructed these names yourself (for example, $(PREFIX)/../filey) then you can use $(dir $(PREFIX))filey instead.
Other than that, there's no way to solve this problem. Make uses string matching on targets and if the strings are not identical, they don't match (there's a special case to ignore the simple prefix ./) Even if make understood this distinction (by applying abspath itself to each target name, maybe) it would still not help in the face of symbolic links for example.
The only "real" answer would be for make to understand something about the underlying file system (device IDs and inodes for example) that let you talk about files without referring to their pathname. However, in a portable program like make doing this is problematic.

GNAT Programming Suite - source file not found

Ada is still new to me, so I am trying to find my way around the GPS IDE. I asked another question earlier, but I think this problem has precedence over that one, and may be at the root of my trouble.
When I compile, I am getting a long list of *warning: source file ... not found"
In my .gpr file, I have listed all of the spec and body source files and use the following naming scheme:
package Naming is
for Casing use "mixedcase";
for Dot_Replacement use ".";
for Spec_Suffix ("ada") use "_s.ada";
for Body_Suffix ("ada") use "_b.ada";
end Naming;
What is odd it the error messages all look either like this:
warning: source file "xxx_b.adb" not found
or this
warning: source file "xxx.adb" not found
Note that neither of these (xxxb.adb or xxx.adb) conform to the file specs, which should end with .ada.
Can someone explain what is going on here?
I'm 99% sure that the problem is one of the ones I mentioned in answer to your other question: GNAT does not normally support more than one compilation unit in a file. I got exactly the behaviour you describe with GPS and these files:
james_s.ada:
with Jane;
package James is
end James;
jim_s.ada:
package Jim is
end Jim;
package Jane is
end Jane;
The error message on compiling james_s.ada says it can't find Jane_s.ada, but when I ask GPS to go to the declaration of Jane it takes me to the "correct" line in jim_s.ada.
You could use gnatchop to split jim_s.ada, but it doesn't understand project files or naming conventions; you probably want to keep the existing names for the code that works, so you'd rename gnatchop's output as required.
However! to my great surprise, it turns out that GNAT does support having more than one compilation unit in a file, provided package Naming in the project file tells it about each unit in the file:
package Naming is
for Casing use "mixedcase";
for Dot_Replacement use ".";
for Spec_Suffix ("ada") use "_s.ada";
for Body_Suffix ("ada") use "_b.ada";
for Spec ("Jim") use "jim_s.ada" at 1;
for Spec ("Jane") use "jim_s.ada" at 2;
end Naming;
It's up to you whether to do this or to bite the bullet and use gnatchop, either on the multi-unit files or on the whole source tree.
First off, this isn't an Ada problem, its a Gnat problem. Other Ada compilers have no problem with the file names you are using.
However, Gnat is rather unique in that it expects there to be only one program unit (package body, package spec, stand-alone routine, etc) per source file. This is because it is also rather unique in that it expects to be able to find the source code for any program unit just by knowing that unit's Ada intentifier. Most other Ada compilers maintain some kind of library file that maps file names to program units, and you have to register all your files into it. (Whereas your typcial C compiler just leaves the problem of finding files for all your code up to the user entirely).
Generally the easiest thing to do with Gnat, the way that will cause you the least trouble, is to just use its default file naming convention (and of course don't put multiple program units in a single file.
If you already have some existing Ada code (perhaps developed for another compiler), the easiest way to import it into Gnat is typically to run the gnatchop tool on it all. So that's what I'd suggest you try.
From GPRbuild User's Guide:
Strings are used for values of attributes or as indexes for these attributes. They are in general case sensitive, except when noted otherwise [...]
Based on this, I believe you have to use "Ada" instead of "ada" as index for Spec_Suffix and Body_Suffix. I currently do not have access to the tools for testing this, so I suggest to just try it out.

Error in Ada separate file

I am translating a Ada83 to Ada95 file. The problem happens when I try to compile a file which calls a separate. The error is "Illegal character " and refers to directive to preprocessor:
with BAS_PUT;
#if ADA_COMPILER="GNAT" then
WITH ADA.GNAT_PUT;
#else
WITH ADA_PUT;
#end if;
separate(A_CALL_PUT)
procedure ....
This problem does not happen when the same preprocessor directive is in a file adb that it is not a separate function.
Someone can help me???
Ada has no preprocessor, so # is indeed an illegal character.
Some compilers (eg: Gnat) do come with one, but if so it is one of their own devising. If you like you can set up your build system to run your Ada source files through external preprocessor (eg: the C pre-processor). I've never done that, but I'm told its eminently doable.
If your compiler does happen to come with a preprocessor, it is non-standard. Use it if you like, but by definition it will be useless for creating portable source files (which appears to be what you are trying to do with it).
Most folks would consider it better form to just create different source files for your different environments, and have the build environment (make rules?) switch between them.

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