[PATCH 0/1] MR5748: winegcc: do not add timestamp to allow reproducible builds

[Marcus Meissner (＠msmeissn)]

The PE abi does not require them for binaries.

Signed-off-by: Marcus Meissner

[PATCH 1/1] winegcc: do not add timestamp to allow reproducible builds

[Marcus Meissner]

From: Marcus Meissner

The PE abi does not require them for binaries.

Signed-off-by: Marcus Meissner 
---
 tools/winegcc/winegcc.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/tools/winegcc/winegcc.c b/tools/winegcc/winegcc.c
index fb759063da9..6de0cf85a44 100644
--- a/tools/winegcc/winegcc.c
+++ b/tools/winegcc/winegcc.c
@@ -403,7 +403,11 @@ static struct strarray get_link_args( struct options *opts, const char *output_n
             strarray_add( &flags, "-shared" );
             strarray_add( &flags, "-Wl,--kill-at" );
         }
-        else strarray_add( &flags, opts->gui_app ? "-mwindows" : "-mconsole" );
+        else
+	{
+	    strarray_add( &flags, opts->gui_app ? "-mwindows" : "-mconsole" );
+	    strarray_add( &flags, "-Wl,--no-insert-timestamp" );
+	}

if (opts->unicode_app) strarray_add( &flags, "-municode" );
         if (opts->nodefaultlibs || opts->use_msvcrt) strarray_add( &flags, "-nodefaultlibs" );

[eric pouech (＠epo)]

Hi Marcus

the drawback of having a zero timestamp is that is will likely generate collisions when storing PE modules in a symbol store (the keys used for storing are: filename, file size (rounded to page size IIRC), and timestamp))

for repro build, we should either:
- pass the timestamp as an external item and let winegcc handles it (setting SOURCE_DATE_EPOCH env var should do, or option --insert-timestamp)
- implement in binutils/ld what MS linker does for repro builds: the PE timestamp is set to a hash of generated file

[Brendan Shanks (＠bshanks)]

I believe binutils 2.42 now honors SOURCE_DATE_EPOCH for the PE timestamp, if you want reproducible builds you would likely be building with that already.

It would be nice if binutils used a hash by default, the MS linker and LLVM lld already do this.

[Paul Gofman (＠gofman)]

IIRC there also were some DRMs which don't like zero timestamp field.

[PATCH 0/1] MR5748: winegcc: do not add timestamp to allow reproducible builds - closed

[Marcus Meissner (＠msmeissn)]

This merge request was closed by Marcus Meissner.

[Marcus Meissner (＠msmeissn)]

then lets close and see if binutils does it.

mingw64-cross-binutils-utils-2.39 is currently used in openSUSE.

I think we will get there when its updated.