summaryrefslogtreecommitdiff
path: root/service_solahart_jakarta_selatan__082122541663/gnat.mdwn
blob: c3d2d10917a00ed3287e8be8843d195fc1f595dc (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
[[!meta copyright="Copyright © 2011, 2012, 2013 Free Software Foundation,
Inc."]]

[[!meta license="""[[!toggle id="license" text="GFDL 1.2+"]][[!toggleable
id="license" text="Permission is granted to copy, distribute and/or modify this
document under the terms of the GNU Free Documentation License, Version 1.2 or
any later version published by the Free Software Foundation; with no Invariant
Sections, no Front-Cover Texts, and no Back-Cover Texts.  A copy of the license
is included in the section entitled [[GNU Free Documentation
License|/fdl]]."]]"""]]

[[!meta title="Enable Ada programming (GCC: GNAT)"]]

[[!tag open_issue_gcc]]

Make the Ada programming language available on GNU/Hurd in its [[service_solahart_jakarta_selatan__082122541663/Gcc]] GNAT
implementation, and enable Hurd-specific features.

There is a [[!FF_project 259]][[!tag bounty]] on this task.

---


# Part I

First, make the language functional, have its test suite pass without errors.


## Original [[community/GSoC]] Task Description

[[!inline pages=community/gsoc/project_ideas/gnat feeds=no]]


## Debian GCC

There has a patch been added for GNU/kFreeBSD:
`bfe081336914729fc0180c07ab4afa41965100f2`, `git-svn-id:
svn://svn.debian.org/gcccvs/branches/sid@5638
6ca36cf4-e1d1-0310-8c6f-e303bb2178ca'


## IRC, freenode, #hurd, 2012-07-17

    <gnu_srs> I've found the remaining problem with gnat backtrace for Hurd!
      Related to the stack frame.
    <gnu_srs> This version does not work: one relying on static assumptions
      about the frame layout
    <gnu_srs> Causing segfaults.
    <gnu_srs> Any interest to create a test case out of that piece of code,
      taken from gcc/ada/tracebak.c?
    <braunr> gnu_srs: sure


### IRC, freenode, #hurd, 2012-07-18

    <braunr> "Digging further revealed that the GNU/Hurd stack frame does not
      seem to
    <braunr> be static enough to define USE_GENERIC_UNWINDER in
      gcc/ada/tracebak.c.
    <braunr> "
    <braunr> what do you mean by a "stack frame does not seem to be static
      enough" ?
    <gnu_srs> I can qoute from the source file if you want. Otherwise look at
      the code yourself: gcc/ada/tracebak,c
    <gnu_srs> I mean that something is wrong with the stack frame for
      Hurd. This is the code I wanted to use as a test case for the stack.
    <gnu_srs> Remember?
    <braunr> more or less
    <braunr> ah, "static assumptions"
    <braunr> all right, i don't think anything is "wrong" with stack frames
    <braunr> but if you use a recent version of gcc, as indicated in the code,
      -fomit-frame-pointer is enabled by default
    <braunr> so your stack frame won't look like it used to be without the
      option
    <braunr> hence the need for USE_GCC_UNWINDER
    <braunr> http://en.wikipedia.org/wiki/Call_stack explains this very well
    <gnu_srs> However, kfreebsd does not seem to need USE_GCC_UNWINDER, how
      come?
    <braunr> i guess they don't omit the frame pointer
    <braunr> your fix is good btw
    <gnu_srs> thanks


### IRC, freenode, #hurd, 2012-07-19

    <gnu_srs> tschwinge: The bug in #681998 should go upstream. Applied in
      Debian already. Hopefully this is the last patch needed for the port of
      GNAT to Hurd.


## Svante's patch

A basic port has been done by Svante, [[!debbug 668425]], [[!debbug 681998]],
[[!message-id "1333104917.2962.439.camel@s1499.it.kth.se"]], but there's still
lots of work remaining.
The port is not yet upstream: the maintainer raised some concerns that
[[I|tschwinge]] have not yet found the time to follow up on, [[!message-id
"1339857758-5032-1-git-send-email-thomas@codesourcery.com"]].
While the test
results of the GCC/GNAT testsuite don't look bad (but there are a few
unresolved issues, and the testsuite appears to be a rather small one), I don't
know if the port has yet seen any real-world usage, such as using it for any
bigger Ada code bases, or any Ada testsuites.


## `getcontext`/`makecontext`/`setcontext`/`swapcontext` usage analysis

In context of [[service_solahart_jakarta_selatan__082122541663/glibc/t/tls-threadvar]].  Looking at GCC trunk commit
f6568ea476aa52a6e23c6db43b3e240cde55783a (2013-04-26).

    gcc/ada/init.c:  sigaltstack (&stack, NULL);
    gcc/ada/init.c:      sigaltstack (&stack, NULL);
    gcc/ada/init.c:  sigaltstack (&stack, NULL);
    gcc/ada/s-osinte-aix.ads:   function sigaltstack
    gcc/ada/s-osinte-aix.ads:   pragma Import (C, sigaltstack, "sigaltstack");
    gcc/ada/s-osinte-android.ads:   function sigaltstack
    gcc/ada/s-osinte-android.ads:   pragma Import (C, sigaltstack, "sigaltstack");
    gcc/ada/s-osinte-darwin.ads:   function sigaltstack
    gcc/ada/s-osinte-darwin.ads:   pragma Import (C, sigaltstack, "sigaltstack");
    gcc/ada/s-osinte-freebsd.ads:   function sigaltstack
    gcc/ada/s-osinte-freebsd.ads:   pragma Import (C, sigaltstack, "sigaltstack");
    gcc/ada/s-osinte-hpux.ads:   function sigaltstack
    gcc/ada/s-osinte-hpux.ads:   pragma Import (C, sigaltstack, "sigaltstack");
    gcc/ada/s-osinte-kfreebsd-gnu.ads:   function sigaltstack
    gcc/ada/s-osinte-kfreebsd-gnu.ads:   pragma Import (C, sigaltstack, "sigaltstack");
    gcc/ada/s-osinte-linux.ads:   function sigaltstack
    gcc/ada/s-osinte-linux.ads:   pragma Import (C, sigaltstack, "sigaltstack");
    gcc/ada/s-osinte-rtems.adb:   -- sigaltstack --
    gcc/ada/s-osinte-rtems.adb:   function sigaltstack
    gcc/ada/s-osinte-rtems.adb:   end sigaltstack;
    gcc/ada/s-osinte-rtems.ads:   function sigaltstack
    gcc/ada/s-osinte-solaris-posix.ads:   function sigaltstack
    gcc/ada/s-osinte-solaris-posix.ads:   pragma Import (C, sigaltstack, "sigaltstack");
    gcc/ada/s-taprop-linux.adb:            Result := sigaltstack (Stack'Access, null);
    gcc/ada/s-taprop-posix.adb:            Result := sigaltstack (Stack'Access, null);
    gcc/ada/init.c:  stack.ss_sp = __gnat_alternate_stack;
    gcc/ada/init.c:      stack.ss_sp = __gnat_alternate_stack;
    gcc/ada/init.c:  stack.ss_sp = __gnat_alternate_stack;
    gcc/ada/s-osinte-aix.ads:      ss_sp    : System.Address;
    gcc/ada/s-osinte-android.ads:      ss_sp    : System.Address;
    gcc/ada/s-osinte-darwin.ads:      ss_sp    : System.Address;
    gcc/ada/s-osinte-darwin.ads:      uc_stack    : stack_t;          --  Stack Used By This Context
    gcc/ada/s-osinte-freebsd.ads:      ss_sp    : System.Address;
    gcc/ada/s-osinte-hpux.ads:      ss_sp    : System.Address;
    gcc/ada/s-osinte-kfreebsd-gnu.ads:      ss_sp    : System.Address;
    gcc/ada/s-osinte-linux.ads:      ss_sp    : System.Address;
    gcc/ada/s-osinte-rtems.ads:      ss_sp    : System.Address;
    gcc/ada/s-osinte-solaris-posix.ads:      ss_sp    : System.Address;
    gcc/ada/s-osinte-solaris.ads:      ss_sp        : System.Address;
    gcc/ada/s-osinte-solaris.ads:      uc_stack     : record_type_2;
    gcc/ada/s-taprop-linux.adb:            Stack.ss_sp    := Self_ID.Common.Task_Alternate_Stack;
    gcc/ada/s-taprop-posix.adb:            Stack.ss_sp    := Self_ID.Common.Task_Alternate_Stack;


---


# Part II

Next, Hurd-specific features can be added.  Add an interface to the
language/environment for being able to do [[RPC]] calls, in order to program
[[hurd/translator]]s natively in Ada.


## Original [[community/GSoC]] Task Description

[[!inline pages=community/gsoc/project_ideas/language_bindings feeds=no]]