[PATCH] ld: Align the PDB DBI source-info substream

[Oleg Tolmatcev]

Round the source-info substream size up to four bytes and zero the
padding.  Extend the test to exercise this case.

ld/
	* pdb.c (create_source_info_substream): Align the substream size and
	zero the padding.
	* testsuite/ld-pe/pdb3b.s: Make the source-info substream require
	padding.
	* testsuite/ld-pe/pdb3-source-info.d: Expect the padding.
---
 ld/pdb.c                              | 5 +++++
 ld/testsuite/ld-pe/pdb3-source-info.d | 2 +-
 ld/testsuite/ld-pe/pdb3b.s            | 3 ++-
 3 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/ld/pdb.c b/ld/pdb.c
index 673d041ce2e..d069549153e 100644
--- a/ld/pdb.c
+++ b/ld/pdb.c
@@ -4391,6 +4391,10 @@ create_source_info_substream (void **data, uint32_t *size,
   *size += sizeof (uint32_t) * source_files_count;
   *size += strings_len;
 
+  /* Subsequent DBI substreams must be 4-byte aligned.  */
+
+  *size = (*size + 3) & ~3u;
+
   *data = xmalloc (*size);
 
   ptr = (uint8_t *) *data;
@@ -4456,6 +4460,7 @@ create_source_info_substream (void **data, uint32_t *size,
 	    }
 	}
     }
+  memset (ptr, 0, (uint8_t *) *data + *size - ptr);
 }
 
 /* Used as parameter to qsort, to sort globals by hash.  */
diff --git a/ld/testsuite/ld-pe/pdb3-source-info.d b/ld/testsuite/ld-pe/pdb3-source-info.d
index 4239c1cb9cf..753a0583b53 100644
--- a/ld/testsuite/ld-pe/pdb3-source-info.d
+++ b/ld/testsuite/ld-pe/pdb3-source-info.d
@@ -4,4 +4,4 @@
 Contents of section .data:
  0000 03000300 00000100 02000200 02000000  ................
  0010 00000000 04000000 04000000 08000000  ................
- 0020 666f6f00 62617200 62617a00           foo.bar.baz.    
+ 0020 666f6f00 62617200 62617a7a 00000000  foo.bar.bazz....
diff --git a/ld/testsuite/ld-pe/pdb3b.s b/ld/testsuite/ld-pe/pdb3b.s
index aa23821648b..f7f70fbad14 100644
--- a/ld/testsuite/ld-pe/pdb3b.s
+++ b/ld/testsuite/ld-pe/pdb3b.s
@@ -17,8 +17,9 @@
 .src1:
 .asciz "bar"
 
+/* Make the unpadded DBI source-info substream size non-aligned.  */
 .src2:
-.asciz "baz"
+.asciz "bazz"
 
 .strings_end:
 
-- 
2.55.0.windows.5