File : par-load.adb
1 ------------------------------------------------------------------------------
2 -- --
3 -- GNAT COMPILER COMPONENTS --
4 -- --
5 -- P A R . L O A D --
6 -- --
7 -- B o d y --
8 -- --
9 -- Copyright (C) 1992-2015, Free Software Foundation, Inc. --
10 -- --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
20 -- --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
23 -- --
24 ------------------------------------------------------------------------------
25
26 -- The Par.Load procedure loads all units that are definitely required before
27 -- it makes any sense at all to proceed with semantic analysis, including
28 -- with'ed units, corresponding specs for bodies, parents of child specs,
29 -- and parents of subunits. All these units are loaded and pointers installed
30 -- in the tree as described in the spec of package Lib.
31
32 with Fname.UF; use Fname.UF;
33 with Lib.Load; use Lib.Load;
34 with Namet.Sp; use Namet.Sp;
35 with Uname; use Uname;
36 with Osint; use Osint;
37 with Sinput.L; use Sinput.L;
38 with Stylesw; use Stylesw;
39 with Validsw; use Validsw;
40
41 with GNAT.Spelling_Checker; use GNAT.Spelling_Checker;
42
43 separate (Par)
44 procedure Load is
45
46 File_Name : File_Name_Type;
47 -- Name of file for current unit, derived from unit name
48
49 Cur_Unum : constant Unit_Number_Type := Current_Source_Unit;
50 -- Unit number of unit that we just finished parsing. Note that we need
51 -- to capture this, because Source_Unit will change as we parse new
52 -- source files in the multiple main source file case.
53
54 Curunit : constant Node_Id := Cunit (Cur_Unum);
55 -- Compilation unit node for current compilation unit
56
57 Loc : Source_Ptr := Sloc (Curunit);
58 -- Source location for compilation unit node
59
60 Save_Style_Check : Boolean;
61 Save_Style_Checks : Style_Check_Options;
62 -- Save style check so it can be restored later
63
64 Save_Validity_Check : Boolean;
65 Save_Validity_Checks : Validity_Check_Options;
66 -- Save validity check so it can be restored later
67
68 With_Cunit : Node_Id;
69 -- Compilation unit node for withed unit
70
71 Context_Node : Node_Id;
72 -- Next node in context items list
73
74 With_Node : Node_Id;
75 -- N_With_Clause node
76
77 Spec_Name : Unit_Name_Type;
78 -- Unit name of required spec
79
80 Body_Name : Unit_Name_Type;
81 -- Unit name of corresponding body
82
83 Unum : Unit_Number_Type;
84 -- Unit number of loaded unit
85
86 Limited_With_Found : Boolean := False;
87 -- We load the context items in two rounds: the first round handles normal
88 -- withed units and the second round handles Ada 2005 limited-withed units.
89 -- This is required to allow the low-level circuitry that detects circular
90 -- dependencies of units the correct notification of errors (see comment
91 -- bellow). This variable is used to indicate that the second round is
92 -- required.
93
94 function Same_File_Name_Except_For_Case
95 (Expected_File_Name : File_Name_Type;
96 Actual_File_Name : File_Name_Type) return Boolean;
97 -- Given an actual file name and an expected file name (the latter being
98 -- derived from the unit name), determine if they are the same except for
99 -- possibly different casing of letters.
100
101 ------------------------------------
102 -- Same_File_Name_Except_For_Case --
103 ------------------------------------
104
105 function Same_File_Name_Except_For_Case
106 (Expected_File_Name : File_Name_Type;
107 Actual_File_Name : File_Name_Type) return Boolean
108 is
109 begin
110 Get_Name_String (Actual_File_Name);
111 Canonical_Case_File_Name (Name_Buffer (1 .. Name_Len));
112
113 declare
114 Lower_Case_Actual_File_Name : String (1 .. Name_Len);
115
116 begin
117 Lower_Case_Actual_File_Name := Name_Buffer (1 .. Name_Len);
118 Get_Name_String (Expected_File_Name);
119 Canonical_Case_File_Name (Name_Buffer (1 .. Name_Len));
120 return Lower_Case_Actual_File_Name = Name_Buffer (1 .. Name_Len);
121 end;
122
123 end Same_File_Name_Except_For_Case;
124
125 -- Start of processing for Load
126
127 begin
128 -- Don't do any loads if we already had a fatal error
129
130 if Fatal_Error (Cur_Unum) = Error_Detected then
131 return;
132 end if;
133
134 Save_Style_Check_Options (Save_Style_Checks);
135 Save_Style_Check := Opt.Style_Check;
136
137 Save_Validity_Check_Options (Save_Validity_Checks);
138 Save_Validity_Check := Opt.Validity_Checks_On;
139
140 -- If main unit, set Main_Unit_Entity (this will get overwritten if
141 -- the main unit has a separate spec, that happens later on in Load)
142
143 if Cur_Unum = Main_Unit then
144 Main_Unit_Entity := Cunit_Entity (Main_Unit);
145 end if;
146
147 -- If we have no unit name, things are seriously messed up by previous
148 -- errors, and we should not try to continue compilation.
149
150 if Unit_Name (Cur_Unum) = No_Unit_Name then
151 raise Unrecoverable_Error;
152 end if;
153
154 -- Next step, make sure that the unit name matches the file name
155 -- and issue a warning message if not. We only output this for the
156 -- main unit, since for other units it is more serious and is
157 -- caught in a separate test below. We also inhibit the message in
158 -- multiple unit per file mode, because in this case the relation
159 -- between file name and unit name is broken.
160
161 File_Name :=
162 Get_File_Name
163 (Unit_Name (Cur_Unum),
164 Subunit => Nkind (Unit (Cunit (Cur_Unum))) = N_Subunit);
165
166 if Cur_Unum = Main_Unit
167 and then Multiple_Unit_Index = 0
168 and then File_Name /= Unit_File_Name (Cur_Unum)
169 and then (File_Names_Case_Sensitive
170 or not Same_File_Name_Except_For_Case
171 (File_Name, Unit_File_Name (Cur_Unum)))
172 then
173 Error_Msg_File_1 := File_Name;
174 Error_Msg
175 ("??file name does not match unit name, should be{", Sloc (Curunit));
176 end if;
177
178 -- For units other than the main unit, the expected unit name is set and
179 -- must be the same as the actual unit name, or we are in big trouble, and
180 -- abandon the compilation since there are situations where this really
181 -- gets us into bad trouble (e.g. some subunit situations).
182
183 if Cur_Unum /= Main_Unit
184 and then Expected_Unit (Cur_Unum) /= Unit_Name (Cur_Unum)
185 then
186 Loc := Error_Location (Cur_Unum);
187 Error_Msg_File_1 := Unit_File_Name (Cur_Unum);
188 Get_Name_String (Error_Msg_File_1);
189
190 -- Check for predefined file case
191
192 if Name_Len > 1
193 and then Name_Buffer (2) = '-'
194 and then (Name_Buffer (1) = 'a'
195 or else
196 Name_Buffer (1) = 's'
197 or else
198 Name_Buffer (1) = 'i'
199 or else
200 Name_Buffer (1) = 'g')
201 then
202 declare
203 Expect_Name : constant Unit_Name_Type := Expected_Unit (Cur_Unum);
204 Actual_Name : constant Unit_Name_Type := Unit_Name (Cur_Unum);
205
206 begin
207 Error_Msg_Unit_1 := Expect_Name;
208 Error_Msg -- CODEFIX
209 ("$$ is not a predefined library unit!", Loc);
210
211 -- In the predefined file case, we know the user did not
212 -- construct their own package, but we got the wrong one.
213 -- This means that the name supplied by the user crunched
214 -- to something we recognized, but then the file did not
215 -- contain the unit expected. Most likely this is due to
216 -- a misspelling, e.g.
217
218 -- with Ada.Calender;
219
220 -- This crunches to a-calend, which indeed contains the unit
221 -- Ada.Calendar, and we can diagnose the misspelling. This
222 -- is a simple heuristic, but it catches many common cases
223 -- of misspelling of predefined unit names without needing
224 -- a full list of them.
225
226 -- Before actually issuing the message, we will check that the
227 -- unit name is indeed a plausible misspelling of the one we got.
228
229 if Is_Bad_Spelling_Of
230 (Name_Id (Expect_Name), Name_Id (Actual_Name))
231 then
232 Error_Msg_Unit_1 := Actual_Name;
233 Error_Msg -- CODEFIX
234 ("possible misspelling of $$!", Loc);
235 end if;
236 end;
237
238 -- Non-predefined file name case. In this case we generate a message
239 -- and then we quit, because we are in big trouble, and if we try
240 -- to continue compilation, we get into some nasty situations
241 -- (for example in some subunit cases).
242
243 else
244 Error_Msg ("file { does not contain expected unit!", Loc);
245 Error_Msg_Unit_1 := Expected_Unit (Cur_Unum);
246 Error_Msg ("\\expected unit $!", Loc);
247 Error_Msg_Unit_1 := Unit_Name (Cur_Unum);
248 Error_Msg ("\\found unit $!", Loc);
249 end if;
250
251 -- In both cases, remove the unit if it is the last unit (which it
252 -- normally (always?) will be) so that it is out of the way later.
253
254 Remove_Unit (Cur_Unum);
255 end if;
256
257 -- If current unit is a body, load its corresponding spec
258
259 if Nkind (Unit (Curunit)) = N_Package_Body
260 or else Nkind (Unit (Curunit)) = N_Subprogram_Body
261 then
262 Spec_Name := Get_Spec_Name (Unit_Name (Cur_Unum));
263 Unum :=
264 Load_Unit
265 (Load_Name => Spec_Name,
266 Required => False,
267 Subunit => False,
268 Error_Node => Curunit,
269 Corr_Body => Cur_Unum,
270 PMES => (Cur_Unum = Main_Unit));
271
272 -- If we successfully load the unit, then set the spec/body pointers.
273 -- Once again note that if the loaded unit has a fatal error, Load will
274 -- have set our Fatal_Error flag to propagate this condition.
275
276 if Unum /= No_Unit then
277 Set_Library_Unit (Curunit, Cunit (Unum));
278 Set_Library_Unit (Cunit (Unum), Curunit);
279
280 -- If this is a separate spec for the main unit, then we reset
281 -- Main_Unit_Entity to point to the entity for this separate spec
282 -- and this is also where we generate the SCO's for this spec.
283
284 if Cur_Unum = Main_Unit then
285 Main_Unit_Entity := Cunit_Entity (Unum);
286
287 if Generate_SCO then
288 SCO_Record_Raw (Unum);
289 end if;
290 end if;
291
292 -- If we don't find the spec, then if we have a subprogram body, we
293 -- are still OK, we just have a case of a body acting as its own spec
294
295 elsif Nkind (Unit (Curunit)) = N_Subprogram_Body then
296 Set_Acts_As_Spec (Curunit, True);
297 Set_Library_Unit (Curunit, Curunit);
298
299 -- Otherwise we do have an error, repeat the load request for the spec
300 -- with Required set True to generate an appropriate error message.
301
302 else
303 Unum :=
304 Load_Unit
305 (Load_Name => Spec_Name,
306 Required => True,
307 Subunit => False,
308 Error_Node => Curunit);
309 return;
310 end if;
311
312 -- If current unit is a child unit spec, load its parent. If the child unit
313 -- is loaded through a limited with, the parent must be as well.
314
315 elsif Nkind (Unit (Curunit)) = N_Package_Declaration
316 or else Nkind (Unit (Curunit)) = N_Subprogram_Declaration
317 or else Nkind (Unit (Curunit)) in N_Generic_Declaration
318 or else Nkind (Unit (Curunit)) in N_Generic_Instantiation
319 or else Nkind (Unit (Curunit)) in N_Renaming_Declaration
320 then
321 -- Turn style and validity checks off for parent unit
322
323 if not GNAT_Mode then
324 Reset_Style_Check_Options;
325 Reset_Validity_Check_Options;
326 end if;
327
328 Spec_Name := Get_Parent_Spec_Name (Unit_Name (Cur_Unum));
329
330 if Spec_Name /= No_Unit_Name then
331 Unum :=
332 Load_Unit
333 (Load_Name => Spec_Name,
334 Required => True,
335 Subunit => False,
336 Error_Node => Curunit);
337
338 if Unum /= No_Unit then
339 Set_Parent_Spec (Unit (Curunit), Cunit (Unum));
340 end if;
341 end if;
342
343 -- If current unit is a subunit, then load its parent body
344
345 elsif Nkind (Unit (Curunit)) = N_Subunit then
346 Body_Name := Get_Parent_Body_Name (Unit_Name (Cur_Unum));
347 Unum :=
348 Load_Unit
349 (Load_Name => Body_Name,
350 Required => True,
351 Subunit => False,
352 Error_Node => Name (Unit (Curunit)));
353
354 if Unum /= No_Unit then
355 Set_Library_Unit (Curunit, Cunit (Unum));
356 end if;
357 end if;
358
359 -- Now we load with'ed units, with style/validity checks turned off
360
361 if not GNAT_Mode then
362 Reset_Style_Check_Options;
363 Reset_Validity_Check_Options;
364 end if;
365
366 -- Load the context items in two rounds: the first round handles normal
367 -- withed units and the second round handles Ada 2005 limited-withed units.
368 -- This is required to allow the low-level circuitry that detects circular
369 -- dependencies of units the correct notification of the following error:
370
371 -- limited with D;
372 -- with D; with C;
373 -- package C is ... package D is ...
374
375 for Round in 1 .. 2 loop
376 Context_Node := First (Context_Items (Curunit));
377 while Present (Context_Node) loop
378
379 -- During the first round we check if there is some limited-with
380 -- context clause; otherwise the second round will be skipped
381
382 if Nkind (Context_Node) = N_With_Clause
383 and then Round = 1
384 and then Limited_Present (Context_Node)
385 then
386 Limited_With_Found := True;
387 end if;
388
389 if Nkind (Context_Node) = N_With_Clause
390 and then ((Round = 1 and then not Limited_Present (Context_Node))
391 or else
392 (Round = 2 and then Limited_Present (Context_Node)))
393 then
394 With_Node := Context_Node;
395 Spec_Name := Get_Unit_Name (With_Node);
396
397 Unum :=
398 Load_Unit
399 (Load_Name => Spec_Name,
400 Required => False,
401 Subunit => False,
402 Error_Node => With_Node,
403 Renamings => True,
404 With_Node => Context_Node);
405
406 -- If we find the unit, then set spec pointer in the N_With_Clause
407 -- to point to the compilation unit for the spec. Remember that
408 -- the Load routine itself sets our Fatal_Error flag if the loaded
409 -- unit gets a fatal error, so we don't need to worry about that.
410
411 if Unum /= No_Unit then
412 Set_Library_Unit (With_Node, Cunit (Unum));
413
414 -- If the spec isn't found, then try finding the corresponding
415 -- body, since it is possible that we have a subprogram body
416 -- that is acting as a spec (since no spec is present).
417
418 else
419 Body_Name := Get_Body_Name (Spec_Name);
420 Unum :=
421 Load_Unit
422 (Load_Name => Body_Name,
423 Required => False,
424 Subunit => False,
425 Error_Node => With_Node,
426 Renamings => True);
427
428 -- If we got a subprogram body, then mark that we are using
429 -- the body as a spec in the file table, and set the spec
430 -- pointer in the N_With_Clause to point to the body entity.
431
432 if Unum /= No_Unit
433 and then Nkind (Unit (Cunit (Unum))) = N_Subprogram_Body
434 then
435 With_Cunit := Cunit (Unum);
436 Set_Library_Unit (With_Node, With_Cunit);
437 Set_Acts_As_Spec (With_Cunit, True);
438 Set_Library_Unit (With_Cunit, With_Cunit);
439
440 -- If we couldn't find the body, or if it wasn't a body spec
441 -- then we are in trouble. We make one more call to Load to
442 -- require the spec. We know it will fail of course, the
443 -- purpose is to generate the required error message (we prefer
444 -- that this message refer to the missing spec, not the body)
445
446 else
447 Unum :=
448 Load_Unit
449 (Load_Name => Spec_Name,
450 Required => True,
451 Subunit => False,
452 Error_Node => With_Node,
453 Renamings => True);
454
455 -- Here we create a dummy package unit for the missing unit
456
457 Unum := Create_Dummy_Package_Unit (With_Node, Spec_Name);
458 Set_Library_Unit (With_Node, Cunit (Unum));
459 end if;
460 end if;
461 end if;
462
463 Next (Context_Node);
464 end loop;
465
466 exit when not Limited_With_Found;
467 end loop;
468
469 -- Restore style/validity check mode for main unit
470
471 Set_Style_Check_Options (Save_Style_Checks);
472 Opt.Style_Check := Save_Style_Check;
473 Set_Validity_Check_Options (Save_Validity_Checks);
474 Opt.Validity_Checks_On := Save_Validity_Check;
475 end Load;