Add support for packed structs

JohnTitor · Nov 27, 2018 · 3e2ac3a · 3e2ac3a
1 parent 7ca0182
commit 3e2ac3a
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Showing 3 changed files with 35 additions and 0 deletions.
diff --git a/src/lib.rs b/src/lib.rs
@@ -645,6 +645,8 @@ impl TestGenerator {
                 .flag("-Werror")
                 .flag("-Wno-unused-parameter")
                 .flag("-Wno-type-limits")
+                // allow taking address of packed struct members:
+                .flag("-Wno-address-of-packed-member")
                 .flag("-Wno-deprecated-declarations"); // allow deprecated items
         }
 

diff --git a/testcrate/src/t1.h b/testcrate/src/t1.h
@@ -98,10 +98,37 @@ struct Q {
   uint8_t q2;
 };
 
+
 struct T1_conflict_foo {
   int a;
 };
 
 struct T1_conflict{
   int foo;
 };
+
+// test packed structs
+//
+// on msvc there is only pragma pack
+// on clang and gcc there is a packed attribute
+
+#ifdef _MSC_VER
+#pragma pack(push,1)
+#endif
+
+#ifndef _MSC_VER
+#define PACK __attribute__((packed))
+#else
+#define PACK
+#endif
+
+struct Pack {
+  uint8_t a;
+  uint16_t b;
+} PACK;
+
+#undef PACK
+
+#ifdef _MSC_VER
+#pragma pack(pop)
+#endif
diff --git a/testcrate/src/t1.rs b/testcrate/src/t1.rs
@@ -140,3 +140,9 @@ pub struct T1_conflict_foo {
 pub struct T1_conflict {
     pub foo: i32,
 }
+
+#[repr(C, packed)]
+pub struct Pack {
+    pub a: u8,
+    pub b: u16,
+}