| Message ID | patch-5.5-fc02ae52f4a-20221007T092505Z-avarab@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | CodingGuidelines: various C99 updates | expand |
diff --git a/Documentation/CodingGuidelines b/Documentation/CodingGuidelines index 893f960231f..65b608ca0a2 100644 --- a/Documentation/CodingGuidelines +++ b/Documentation/CodingGuidelines @@ -242,6 +242,10 @@ For C programs: printf("%"PRIuMAX, (uintmax_t)v); These days the MSVC version we rely on supports %z, but the C library used by MinGW does not. + . Shorthand like ".a.b = *c" in struct assignments is known to trip + up an older IBM XLC version, use ".a = { .b = *c }" instead. See + the 33665d98e6b portability fix from mid-2022. + - Variables have to be declared at the beginning of the block, before the first statement (i.e. -Wdeclaration-after-statement).
Per 33665d98e6b (reftable: make assignments portable to AIX xlc v12.01, 2022-03-28) forms like ".a.b = *c" can be replaced by using ".a = { .b = *c }" instead. We'll probably allow these sooner than later, but since the workaround is trivial let's note it among the C99 features we'd like to hold off on for now. Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> --- Documentation/CodingGuidelines | 4 ++++ 1 file changed, 4 insertions(+)