| Message ID | alpine.DEB.2.20.1802262152320.2986@digraph.polyomino.org.uk |
|---|---|
| State | New |
| Headers | show |
| Series | Fix two more -Os strcoll / wcscoll build failures | expand |
On 26/02/2018 18:53, Joseph Myers wrote: > Continuing fixes for -Os build issues shown with build-many-glibcs.py, > this patch adds uses of DIAG_* to disable -Wmaybe-uninitialized in two > more places where code inlined from strcoll / wcscoll is wrongly > diagnosed as possibly using uninitialized structure fields. (All > these warnings in different places for these functions are I think > essentially the same bug.) > > Tested with build-many-glibcs.py for alpha-linux-gnu and > mips-linux-gnu that this fixes the -Os build failures for those > configurations with GCC 7. > > 2018-02-26 Joseph Myers <joseph@codesourcery.com> > > * locale/weightwc.h (findidx): Ignore -Wmaybe-uninitialized for > -Os in two more places. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org> > > diff --git a/locale/weightwc.h b/locale/weightwc.h > index ac25ba9..36c65b5 100644 > --- a/locale/weightwc.h > +++ b/locale/weightwc.h > @@ -28,7 +28,15 @@ findidx (const int32_t *table, > const wint_t *extra, > const wint_t **cpp, size_t len) > { > + /* With GCC 7 when compiling with -Os the compiler warns that > + seq1.back_us and seq2.back_us, which become *cpp, might be used > + uninitialized. This is impossible as this function cannot be > + called except in cases where those fields have been > + initialized. */ > + DIAG_PUSH_NEEDS_COMMENT; > + DIAG_IGNORE_Os_NEEDS_COMMENT (7, "-Wmaybe-uninitialized"); > wint_t ch = *(*cpp)++; > + DIAG_POP_NEEDS_COMMENT; > int32_t i = __collidx_table_lookup ((const char *) table, ch); > > if (i >= 0) > @@ -107,11 +115,18 @@ findidx (const int32_t *table, > continue; > } > > + /* With GCC 7 when compiling with -Os the compiler warns > + that seq1.back_us and seq2.back_us, which become usrc, > + might be used uninitialized. This is impossible for the > + same reason as described above. */ > + DIAG_PUSH_NEEDS_COMMENT; > + DIAG_IGNORE_Os_NEEDS_COMMENT (7, "-Wmaybe-uninitialized"); > if (cp[nhere - 1] > usrc[nhere -1]) > { > cp += 2 * nhere; > continue; > } > + DIAG_POP_NEEDS_COMMENT; > > if (cp[2 * nhere - 1] < usrc[nhere -1]) > { >
diff --git a/locale/weightwc.h b/locale/weightwc.h index ac25ba9..36c65b5 100644 --- a/locale/weightwc.h +++ b/locale/weightwc.h @@ -28,7 +28,15 @@ findidx (const int32_t *table, const wint_t *extra, const wint_t **cpp, size_t len) { + /* With GCC 7 when compiling with -Os the compiler warns that + seq1.back_us and seq2.back_us, which become *cpp, might be used + uninitialized. This is impossible as this function cannot be + called except in cases where those fields have been + initialized. */ + DIAG_PUSH_NEEDS_COMMENT; + DIAG_IGNORE_Os_NEEDS_COMMENT (7, "-Wmaybe-uninitialized"); wint_t ch = *(*cpp)++; + DIAG_POP_NEEDS_COMMENT; int32_t i = __collidx_table_lookup ((const char *) table, ch); if (i >= 0) @@ -107,11 +115,18 @@ findidx (const int32_t *table, continue; } + /* With GCC 7 when compiling with -Os the compiler warns + that seq1.back_us and seq2.back_us, which become usrc, + might be used uninitialized. This is impossible for the + same reason as described above. */ + DIAG_PUSH_NEEDS_COMMENT; + DIAG_IGNORE_Os_NEEDS_COMMENT (7, "-Wmaybe-uninitialized"); if (cp[nhere - 1] > usrc[nhere -1]) { cp += 2 * nhere; continue; } + DIAG_POP_NEEDS_COMMENT; if (cp[2 * nhere - 1] < usrc[nhere -1]) {