From f32d49916d41592a790219e0869a3dbc5e1b49f3 Mon Sep 17 00:00:00 2001 From: Raymond Lu Date: Fri, 12 Aug 2011 09:38:30 -0500 Subject: [svn-r21220] The original code i_mask = ~((unsigned)~0 << (precision[0] + offset[0])) & ((unsigned)~0 << offset[0]); in line 3680 left shifted a 32-bit integer for 32-bit. The result is undefined by C language. A user discovered it using clang compiler with -fcatch-undefined-behavior option (see Issue 7674 in Jira). So I changed it in a funny way to avoid it. Tested on jam, koala, and heiwa. --- test/dsets.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) diff --git a/test/dsets.c b/test/dsets.c index 0c62736..959ac43 100644 --- a/test/dsets.c +++ b/test/dsets.c @@ -3664,7 +3664,18 @@ test_nbit_compound_2(hid_t file) /* Check that the values read are the same as the values written * Use mask for checking the significant bits, ignoring the padding bits */ - i_mask = ~((unsigned)~0 << (precision[0] + offset[0])) & ((unsigned)~0 << offset[0]); + /* The original code + * i_mask = ~((unsigned)~0 << (precision[0] + offset[0])) & ((unsigned)~0 << offset[0]); + * left shift a 32-bit integer for 32-bit. The result is undefined by C language. A user + * discovered it using clang compiler with -fcatch-undefined-behavior option (see Issue 7674 + * in Jira). So I changed it in a funny way as below to avoid it. SLU - 2011/8/11 + */ + if(sizeof(unsigned) > 4) + i_mask = ~((unsigned)~0 << (precision[0] + offset[0])) & ((unsigned)~0 << offset[0]); + else { + i_mask = 0xffffffff; + i_mask = i_mask & ((unsigned)~0 << offset[0]); + } c_mask = ~((unsigned)~0 << (precision[1] + offset[1])) & ((unsigned)~0 << offset[1]); s_mask = ~((unsigned)~0 << (precision[2] + offset[2])) & ((unsigned)~0 << offset[2]); b_mask = ~((unsigned)~0 << (precision[4] + offset[4])) & ((unsigned)~0 << offset[4]); -- cgit v0.12