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Diffstat (limited to 'meta/recipes-devtools/gcc/gcc-4.8/0047-repomembug.patch')
-rw-r--r-- | meta/recipes-devtools/gcc/gcc-4.8/0047-repomembug.patch | 53 |
1 files changed, 53 insertions, 0 deletions
diff --git a/meta/recipes-devtools/gcc/gcc-4.8/0047-repomembug.patch b/meta/recipes-devtools/gcc/gcc-4.8/0047-repomembug.patch new file mode 100644 index 0000000000..868a4f3a51 --- /dev/null +++ b/meta/recipes-devtools/gcc/gcc-4.8/0047-repomembug.patch | |||
@@ -0,0 +1,53 @@ | |||
1 | When compiling a project using -frepo, .rpo files are written alongside | ||
2 | the .o file, the symbols either have O or C against them. During final linking, | ||
3 | the objects can be recompiled with some of the entries tweaked/chosen by the | ||
4 | tlink.c code (visible with TLINK_VERBOSE=3), it does this by changing O -> C | ||
5 | in the .rpo files. | ||
6 | |||
7 | My tests showed that init_repo (cp/repo.c) was correctly calling | ||
8 | IDENTIFIER_REPO_CHOSEN against the right identifers and setting the | ||
9 | chosen bit. | ||
10 | |||
11 | By the time finish_repo() or emit_repo_p() were called, the pointer returned | ||
12 | by get_identifier() for the symbol marked during init_repo had changed and | ||
13 | the chosen bit was no longer set. This lead to linking bugs like: | ||
14 | |||
15 | collect: relinking | ||
16 | collect2: error: '_ZNK6sudoku5ClearINS_8SequenceEEclERS1_' was assigned to 'board.rpo', but was not defined during recompilation, or vice versa | ||
17 | |||
18 | The problem is that the garbage collection is getting called before | ||
19 | finish_repo() is called and ggc_protect_identifiers is set to false | ||
20 | so the identifiers are not preserved. They are recreated but the | ||
21 | chosen bits get wiped out which is why the pointer changes and the | ||
22 | chosen bit is not set. | ||
23 | |||
24 | The fix is to change ggc_protect_identifiers *after* the finish_repo | ||
25 | calls are made. | ||
26 | |||
27 | Reproduction is tricky since you need to trigger the garbage collector at | ||
28 | just the right moment. | ||
29 | |||
30 | RP 2013/10/9 | ||
31 | |||
32 | [YOCTO #5133] | ||
33 | |||
34 | Upstream-State: Pending | ||
35 | |||
36 | Index: gcc-4.8.1/gcc/toplev.c | ||
37 | =================================================================== | ||
38 | --- gcc-4.8.1.orig/gcc/toplev.c 2013-03-28 08:29:51.000000000 +0000 | ||
39 | +++ gcc-4.8.1/gcc/toplev.c 2013-10-09 20:27:17.089228023 +0000 | ||
40 | @@ -551,11 +551,11 @@ | ||
41 | if (flag_syntax_only || flag_wpa) | ||
42 | return; | ||
43 | |||
44 | - ggc_protect_identifiers = false; | ||
45 | - | ||
46 | /* This must also call finalize_compilation_unit. */ | ||
47 | lang_hooks.decls.final_write_globals (); | ||
48 | |||
49 | + ggc_protect_identifiers = false; | ||
50 | + | ||
51 | if (seen_error ()) | ||
52 | return; | ||
53 | |||