Commit Graph

10 Commits

Author SHA1 Message Date
Sjoerd Meijer 3d9a0445cc Recommit #2 "[Driver] Default to -fno-common for all targets"
After a first attempt to fix the test-suite failures, my first recommit
caused the same failures again. I had updated CMakeList.txt files of
tests that needed -fcommon, but it turns out that there are also
Makefiles which are used by some bots, so I've updated these Makefiles
now too.

See the original commit message for more details on this change:
0a9fc9233e
2020-03-09 19:57:03 +00:00
Sjoerd Meijer f35d112efd Revert "Recommit "[Driver] Default to -fno-common for all targets""
This reverts commit 2c36c23f34.

Still problems in the test-suite, which I really thought I had fixed...
2020-03-09 10:37:28 +00:00
Sjoerd Meijer 2c36c23f34 Recommit "[Driver] Default to -fno-common for all targets"
This includes fixes for:
- test-suite: some benchmarks need to be compiled with -fcommon, see D75557.
- compiler-rt: one test needed -fcommon, and another a change, see D75520.
2020-03-09 10:07:37 +00:00
Sjoerd Meijer 4e363563fa Revert "[Driver] Default to -fno-common for all targets"
This reverts commit 0a9fc9233e.

Going to look at the asan failures.

I find the failures in the test suite weird, because they look
like compile time test and I don't understand how that can be
failing, but will have a brief look at that too.
2020-03-03 10:00:36 +00:00
Sjoerd Meijer 0a9fc9233e [Driver] Default to -fno-common for all targets
This makes -fno-common the default for all targets because this has performance
and code-size benefits and is more language conforming for C code.
Additionally, GCC10 also defaults to -fno-common and so we get consistent
behaviour with GCC.

With this change, C code that uses tentative definitions as definitions of a
variable in multiple translation units will trigger multiple-definition linker
errors. Generally, this occurs when the use of the extern keyword is neglected
in the declaration of a variable in a header file. In some cases, no specific
translation unit provides a definition of the variable. The previous behavior
can be restored by specifying -fcommon.

As GCC has switched already, we benefit from applications already being ported
and existing documentation how to do this. For example:
- https://gcc.gnu.org/gcc-10/porting_to.html
- https://wiki.gentoo.org/wiki/Gcc_10_porting_notes/fno_common

Differential revision: https://reviews.llvm.org/D75056
2020-03-03 09:15:07 +00:00
Rafael Espindola 922f2aa9b2 Bring r325915 back.
The tests that failed on a windows host have been fixed.

Original message:

Start setting dso_local for COFF.

With this there are still some GVs where we don't set dso_local
because setGVProperties is never called. I intend to fix that in
followup commits. This is just the bare minimum to teach
shouldAssumeDSOLocal what it should do for COFF.

llvm-svn: 325940
2018-02-23 19:30:48 +00:00
Rafael Espindola 43ce3a3a4d Revert "Start setting dso_local for COFF."
This reverts commit r325915.

It will take some time to fix the failures on a windows host.

llvm-svn: 325929
2018-02-23 18:09:29 +00:00
Rafael Espindola 004d240b6a Start setting dso_local for COFF.
With this there are still some GVs where we don't set dso_local
because setGVProperties is never called. I intend to fix that in
followup commits. This is just the bare minimum to teach
shouldAssumeDSOLocal what it should do for COFF.

llvm-svn: 325915
2018-02-23 15:32:32 +00:00
Aaron Ballman 674cf26892 __declspec is not a core Clang language extension. Instead, require -fms-extensions or -fborland to enable the language extension.
Note: __declspec is also temporarily enabled when compiling for a CUDA target because there are implementation details relying on __declspec(property) support currently. When those details change, __declspec should be disabled for CUDA targets.
llvm-svn: 238238
2015-05-26 19:44:52 +00:00
Saleem Abdulrasool 8ab3e83efa CodeGen: support dll{ex,im}port on WoA
Add ARM support for dllexport and dllimport attributes.  This is a relatively
conservative change.  The alternative is to entirely drop the architecture
requirement.  The dllimport and dllexport attributes are not restricted to any
architecture, simply to platforms that support this attribute (currently
Windows).

llvm-svn: 208486
2014-05-11 01:31:57 +00:00