Mercurial > hg > octave-lojdl > gnulib-hg
changeset 17002:0103491fe167
verify: document conflict with -Wnested-externs
Our implementation of verify() relies on nested extern declarations,
so it is incompatible with gcc < 4.6 coupled with -Wnested-externs
when used inside a function body. But inside a function body, you
can always arrange to use verify_expr() instead, which is warning-free.
* lib/verify.h: Give hint about usage when gcc warnings are enabled.
Signed-off-by: Eric Blake <eblake@redhat.com>
| author | Eric Blake <eblake@redhat.com> |
|---|---|
| date | Fri, 20 Jul 2012 16:48:46 -0600 |
| parents | 47d115143a81 |
| children | 13795cd8c0ba |
| files | ChangeLog lib/verify.h |
| diffstat | 2 files changed, 8 insertions(+), 1 deletions(-) [+] |
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--- a/ChangeLog +++ b/ChangeLog @@ -1,5 +1,8 @@ 2012-07-20 Eric Blake <eblake@redhat.com> + verify: document conflict with -Wnested-externs + * lib/verify.h: Give hint about usage when gcc warnings are enabled. + maint.mk: forbid exit(-1) * top/maint.mk (sc_prohibit_magic_number_exit): Detect negatives.
--- a/lib/verify.h +++ b/lib/verify.h @@ -125,7 +125,7 @@ extern int (*dummy (void)) [sizeof (struct {...})]; * GCC warns about duplicate declarations of the dummy function if - -Wredundant_decls is used. GCC 4.3 and later have a builtin + -Wredundant-decls is used. GCC 4.3 and later have a builtin __COUNTER__ macro that can let us generate unique identifiers for each dummy function, to suppress this warning. @@ -133,6 +133,10 @@ which do not support _Static_assert, also do not warn about the last declaration mentioned above. + * GCC warns if -Wnested-externs is enabled and verify() is used + within a function body; but inside a function, you can always + arrange to use verify_expr() instead. + * In C++, any struct definition inside sizeof is invalid. Use a template type to work around the problem. */