diff mbox series

[committed] d: Respect explicit align(N) type alignment (PR100935)

Message ID 20210609180501.3203740-1-ibuclaw@gdcproject.org
State New
Headers show
Series [committed] d: Respect explicit align(N) type alignment (PR100935) | expand

Commit Message

Iain Buclaw June 9, 2021, 6:05 p.m. UTC 
Hi,

This patch fixes the .alignof property to report the correct alignment
if an explicit one was given for the type.

It was previously the natural type alignment, defined as the maximum of
the field alignments for an aggregate.  Make sure an explicit align(N)
overrides it.

Bootstrapped and regression tested on x86_64-linux-gnu/-m32/-mx32,
committed to mainline, and backported to the gcc-9, gcc-10, and gcc-11
release branches.

Regards,
Iain.

---
gcc/d/ChangeLog:

	PR d/100935
	* dmd/MERGE: Merge upstream dmd f3fdeb578.
---
 gcc/d/dmd/MERGE                               |  2 +-
 gcc/d/dmd/mtype.c                             |  5 ++++-
 .../gdc.test/compilable/aggr_alignment.d      | 20 +++++++++++++++++++
 3 files changed, 25 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/gcc/d/dmd/MERGE b/gcc/d/dmd/MERGE
index d29d462f42f..e22e3d1ebf7 100644
--- a/gcc/d/dmd/MERGE
+++ b/gcc/d/dmd/MERGE
@@ -1,4 +1,4 @@ 
-b7d146c4c34469f876a63f26ff19091a7f9d54d7
+f3fdeb578f8cc6d9426d47d2fa144d2078f9ab29
 
 The first line of this file holds the git revision number of the last
 merge done from the dlang/dmd repository.
diff --git a/gcc/d/dmd/mtype.c b/gcc/d/dmd/mtype.c
index 9ef8ab4e5f4..6cccf40df98 100644
--- a/gcc/d/dmd/mtype.c
+++ b/gcc/d/dmd/mtype.c
@@ -2040,7 +2040,10 @@  Expression *Type::getProperty(Loc loc, Identifier *ident, int flag)
     }
     else if (ident == Id::__xalignof)
     {
-        e = new IntegerExp(loc, alignsize(), Type::tsize_t);
+        unsigned explicitAlignment = alignment();
+        unsigned naturalAlignment = alignsize();
+        unsigned actualAlignment = (explicitAlignment == STRUCTALIGN_DEFAULT ? naturalAlignment : explicitAlignment);
+        e = new IntegerExp(loc, actualAlignment, Type::tsize_t);
     }
     else if (ident == Id::_init)
     {
diff --git a/gcc/testsuite/gdc.test/compilable/aggr_alignment.d b/gcc/testsuite/gdc.test/compilable/aggr_alignment.d
index bf602ff31a4..0c727e2fec5 100644
--- a/gcc/testsuite/gdc.test/compilable/aggr_alignment.d
+++ b/gcc/testsuite/gdc.test/compilable/aggr_alignment.d
@@ -27,6 +27,26 @@  static assert(C2.int1.offsetof == payloadOffset + 8);
 static assert(C2.alignof == size_t.sizeof);
 static assert(__traits(classInstanceSize, C2) == payloadOffset + 12);
 
+align(8) struct PaddedStruct
+{
+    bool flag;
+    align(2) S1 s1;
+}
+
+static assert(PaddedStruct.s1.offsetof == 2);
+static assert(PaddedStruct.alignof == 8);
+static assert(PaddedStruct.sizeof == 16);
+
+align(1) struct UglyStruct
+{
+    bool flag;
+    int i;
+    ubyte u;
+}
+
+static assert(UglyStruct.i.offsetof == 4);
+static assert(UglyStruct.alignof == 1);
+static assert(UglyStruct.sizeof == 9);
 
 /***************************************************/
 // https://issues.dlang.org/show_bug.cgi?id=19914