llvm-project

Commit Graph

Author	SHA1	Message	Date
Rafael Espindola	464fe024c5	Use "weak alias" instead of "alias weak" Before this patch we had @a = weak global ... but @b = alias weak ... The patch changes aliases to look more like global variables. Looking at some really old code suggests that the reason was that the old bison based parser had a reduction for alias linkages and another one for global variable linkages. Putting the alias first avoided the reduce/reduce conflict. The days of the old .ll parser are long gone. The new one parses just "linkage" and a later check is responsible for deciding if a linkage is valid in a given context. llvm-svn: 214355	2014-07-30 22:51:54 +00:00
Rafael Espindola	f3336bc1d5	Reject alias to undefined symbols in the verifier. On ELF and COFF an alias is just another name for a position in the file. There is no way to refer to a position in another file, so an alias to undefined is meaningless. MachO currently doesn't support aliases. The spec has a N_INDR, which when implemented will have a different set of restrictions. Adding support for it shouldn't be harder than any other IR extension. For now, having the IR represent what is actually possible with current tools makes it easier to fix the design of GlobalAlias. llvm-svn: 203705	2014-03-12 20:15:49 +00:00
Duncan Sands	b40654e21d	Testcase for PR10663. llvm-svn: 138231	2011-08-22 10:32:09 +00:00

Author

SHA1

Message

Date

Rafael Espindola

464fe024c5

Use "weak alias" instead of "alias weak"

Before this patch we had

@a = weak global ...
but
@b = alias weak ...

The patch changes aliases to look more like global variables.

Looking at some really old code suggests that the reason was that the old
bison based parser had a reduction for alias linkages and another one for
global variable linkages. Putting the alias first avoided the reduce/reduce
conflict.

The days of the old .ll parser are long gone. The new one parses just "linkage"
and a later check is responsible for deciding if a linkage is valid in a
given context.

llvm-svn: 214355

2014-07-30 22:51:54 +00:00

Rafael Espindola

f3336bc1d5

Reject alias to undefined symbols in the verifier.

On ELF and COFF an alias is just another name for a position in the file.
There is no way to refer to a position in another file, so an alias to
undefined is meaningless.

MachO currently doesn't support aliases. The spec has a N_INDR, which when
implemented will have a different set of restrictions. Adding support for
it shouldn't be harder than any other IR extension.

For now, having the IR represent what is actually possible with current
tools makes it easier to fix the design of GlobalAlias.

llvm-svn: 203705

2014-03-12 20:15:49 +00:00

Duncan Sands

b40654e21d

Testcase for PR10663.

llvm-svn: 138231

2011-08-22 10:32:09 +00:00

3 Commits