From: Daniel Dunbar Date: Wed, 13 May 2009 21:34:08 +0000 (+0000) Subject: Add a test case to showcase a difference in #pragma pack handling X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=1faf5baa2f5e1adecb289679fe41c8a5080e4611;p=clang Add a test case to showcase a difference in #pragma pack handling compared to gcc. This is worrisome, but I believe we are doing the "correct" thing, and if I recall correctly I previously verified this versus MSVC. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@71723 91177308-0d34-0410-b5e6-96231b3b80d8 --- diff --git a/test/Sema/pragma-pack-3.c b/test/Sema/pragma-pack-3.c new file mode 100644 index 0000000000..a2d665ea74 --- /dev/null +++ b/test/Sema/pragma-pack-3.c @@ -0,0 +1,34 @@ +// RUN: clang-cc -triple i686-apple-darwin9 %s -fsyntax-only -verify + +// Stack: [], Alignment: 8 + +#pragma pack(push, 1) +// Stack: [8], Alignment: 1 + +#pragma pack(push, 4) +// Stack: [8, 1], Alignment: 4 + +// Note that this differs from gcc; pack() in gcc appears to pop the +// top stack entry and resets the current alignment. This is both +// inconsistent with MSVC, and the gcc documentation. In other cases, +// for example changing this to pack(8), I don't even understand what gcc +// is doing. + +#pragma pack() +// Stack: [8, 1], Alignment: 8 + +#pragma pack(pop) +// Stack: [8], Alignment: 1 +struct s0 { + char f0; + short f1; +}; +int a[sizeof(struct s0) == 3 ? 1 : -1]; + +#pragma pack(pop) +// Stack: [], Alignment: 8 +struct s1 { + char f0; + short f1; +}; +int b[sizeof(struct s1) == 4 ? 1 : -1];