5439 – 64bit struct alignment inconsistent with C ABI

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Issue 5439 - 64bit struct alignment inconsistent with C ABI

Summary: 64bit struct alignment inconsistent with C ABI

Keywords:
Status:	RESOLVED FIXED
Alias:	None
Product:	D
Classification:	Unclassified
Component:	dmd (show other issues)
Version:	D2
Hardware:	x86_64 Linux
Importance :	P2 normal
Assignee:	No Owner
URL:
Depends on:
Blocks:

See Also:
Reported:	2011年01月09日 11:03 UTC by Iain Buclaw
Modified:	2015年06月09日 05:12 UTC (History)
CC List:	2 users (show)

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Description Iain Buclaw 2011年01月09日 11:03:22 UTC

This was caused by bug2821. On 64bit, doubles are 8-byte aligned, not 4, so
struct { long, short }
Should have a sizeof = 16, not 12.
Btw, would be nice if you offered a -malign-double type flag to say "Yes, I want 8 byte aligned doubles on 32bit Linux" :)
Regards

Comment 1 Iain Buclaw 2011年01月09日 11:05:08 UTC

To save you searching for it, lookup "TypeBasic::alignsize"

Comment 2 Walter Bright 2011年01月11日 00:05:55 UTC

http://www.dsource.org/projects/dmd/changeset/861