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author | Dodji Seketeli <dodji@redhat.com> | 2012-06-04 19:19:58 +0000 |
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committer | Dodji Seketeli <dodji@gcc.gnu.org> | 2012-06-04 21:19:58 +0200 |
commit | 7ca643e17ea01be20f1bfd91091ff658ff23bc3d (patch) | |
tree | 21b0dd6452ab80ed34b7dec7d98597cf279e3564 /libcpp/line-map.c | |
parent | aadd9700d5a475c506a11b3d1ab8b20c89b63b45 (diff) | |
download | gcc-7ca643e17ea01be20f1bfd91091ff658ff23bc3d.zip gcc-7ca643e17ea01be20f1bfd91091ff658ff23bc3d.tar.gz gcc-7ca643e17ea01be20f1bfd91091ff658ff23bc3d.tar.bz2 |
PR preprocessor/53463 - Fix system header detection for built-in macro tokens
The location for a built-in macro token is BUILTIN_LOCATION. When we
see that location value, we cannot know if that token was used in a
system header or not. And that can trigger some unwanted warnings on
e.g, the use of __LONG_LONG_MAX__ built-in macro in system headers
when we compile with -pedantic, like in the test case accompanying
this patch.
In that case, I think we ought to step-up to see where the built-in
macro has been expanded, until we see a location that is not for a
built-in macro. Then we can check if the resulting location is in a
system header or not.
Now that we step up to the location of first non-built-in-macro token,
it appeared that for
testsuite/c-c++-common/dfp/convert-int-saturate.c, G++ then fails to
emit the warning in:
volatile unsigned int usi;
int
main ()
{
usi = DEC32_MAX; /* { dg-warning "overflow in implicit constant conversion" } */
...
}
Because DEC32_MAX is defined in the system header float.h as a
built-in macro:
#define DEC32_MAX __DEC32_MAX__
And during the parsing of the assignment expression that should have
led to the warning above, input_location is set to the location for
the DEC32_MAX, which is actually the location for the built-in
__DECL32_MAX_EXP.
A possible fix is to use the location of the "=" operator as the
default location for assignment expressions. This is what the patch
does.
I had to adjust a couple of tests to arrange for this.
Bootstrapped and tested on x86_64-unknown-linux-gnu against trunk.
libcpp/
PR preprocessor/53463
* line-map.c (linemap_location_in_system_header_p): For built-in
macro tokens, check the first expansion point location for that is
not for a token coming from a built-in macro.
gcc/cp/
PR preprocessor/53463
* parser.c (cp_parser_assignment_expression): Use the location
for the LHS as the default location for the expression.
gcc/testsuite/
PR preprocessor/53463
* g++.dg/cpp/limits.C: New test.
* g++.dg/parse/error19.C: Adjust.
* g++.dg/warn/Wconversion-real-integer2.C: Likewise.
* g++.dg/warn/pr35635.C: Likewise.
* g++.old-deja/g++.pt/assign1.C: Likewise.
From-SVN: r188203
Diffstat (limited to 'libcpp/line-map.c')
-rw-r--r-- | libcpp/line-map.c | 30 |
1 files changed, 26 insertions, 4 deletions
diff --git a/libcpp/line-map.c b/libcpp/line-map.c index 8a368ee..e6a344f 100644 --- a/libcpp/line-map.c +++ b/libcpp/line-map.c @@ -755,13 +755,35 @@ linemap_location_in_system_header_p (struct line_maps *set, { const struct line_map *map = NULL; - location = - linemap_resolve_location (set, location, LRK_SPELLING_LOCATION, &map); - if (location < RESERVED_LOCATION_COUNT) return false; - return LINEMAP_SYSP (map); + /* Let's look at where the token for LOCATION comes from. */ + while (true) + { + map = linemap_lookup (set, location); + if (map != NULL) + { + if (!linemap_macro_expansion_map_p (map)) + /* It's a normal token. */ + return LINEMAP_SYSP (map); + else + { + /* It's a token resulting from a macro expansion. */ + source_location loc = + linemap_macro_map_loc_unwind_toward_spelling (map, location); + if (loc < RESERVED_LOCATION_COUNT) + /* This token might come from a built-in macro. Let's + look at where that macro got expanded. */ + location = linemap_macro_map_loc_to_exp_point (map, location); + else + location = loc; + } + } + else + break; + } + return false; } /* Return TRUE if LOCATION is a source code location of a token coming |