https://gcc.gnu.org/bugzilla/show_bug.cgi?id=34747
Martin Sebor <msebor at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|UNCONFIRMED |RESOLVED CC| |msebor at gcc dot gnu.org Blocks| |58601 Resolution|--- |DUPLICATE --- Comment #5 from Martin Sebor <msebor at gcc dot gnu.org> --- When compiled with the current trunk (7.0), the test produces the output below (same as in comment #4). After reviewing the tests I believe all the failures are false positives. The failing tests assume that a #pragma pack directive doesn't affect the alignment of struct members. However, according to GCC documentation for attribute packed: "Specifying this attribute [packed] for struct and union types is equivalent to specifying the packed attribute on each of the structure or union members." And specifying the attribute on a member reduces its alignment to the one specified. So test5, for instance, expects the alignment of a struct defined just following #pragma pack not to be affected by the #pragma. Similarly for all the other failing tests. Since the valid tests pass (fixed by PR 10179) I'll go ahead and close this report as a duplicate of that bug. (Based on the summary of this I'm assuming the expectation is that #pragma pack have the same effect as attribute packed and not something else.) FAILED: test5 FAILED: test7 FAILED: test20 FAILED: test21 FAILED: test25 FAILED: test26 FAILED: test37 FAILED: test46 FAILED: test47 FAILED: test48 10 tests failed! *** This bug has been marked as a duplicate of bug 10179 *** Referenced Bugs: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58601 [Bug 58601] [meta-bug] alignas