Documentation, tests for hsc2hs's new #alignment macro

Adds two tests (one for Trac #4340 and one for Trac #10272), as well as
advice on how to fix your code if `hsc2hs` emits warnings with GHC 8.0
due to a redefinition of `#alignment`. (I also put the advice in the
[GHC 8.0 Migration
Guide](https://ghc.haskell.org/trac/ghc/wiki/Migration/8.0).)

Reviewed By: thomie

Differential Revision: https://phabricator.haskell.org/D1663

GHC Trac Issues: #4340, #10272

7 files changed, 50 insertions, 0 deletions

diff --git a/testsuite/tests/hsc2hs/Makefile b/testsuite/tests/hsc2hs/Makefile
index ec16b16474..54fa5ad8a0 100644
--- a/testsuite/tests/hsc2hs/Makefile
+++ b/testsuite/tests/hsc2hs/Makefile
@@ -28,3 +28,15 @@ hsc2hs004:
 T3837:
 	LANG=C '$(HSC2HS)' $@.hsc
 	'$(TEST_HC)' $(TEST_HC_OPTS) -c $@.hs
+
+.PHONY: T4340
+T4340:
+	'$(HSC2HS)' $@.hsc
+	'$(TEST_HC)' $(TEST_HC_OPTS) -v0 --make $@
+	./$@
+
+.PHONY: T10272
+T10272:
+	'$(HSC2HS)' --cross-compile $@.hsc
+	'$(TEST_HC)' $(TEST_HC_OPTS) -v0 --make $@
+	./$@
diff --git a/testsuite/tests/hsc2hs/T10272.h b/testsuite/tests/hsc2hs/T10272.h
new file mode 100644
index 0000000000..6d8142d909
--- /dev/null
+++ b/testsuite/tests/hsc2hs/T10272.h
@@ -0,0 +1,12 @@
+#ifndef _T10272_H_
+#define _T10272_H_
+
+#include <stdint.h>
+
+typedef struct {
+  uint8_t  a;
+  uint64_t b;
+  uint16_t c;
+} eight;
+
+#endif
diff --git a/testsuite/tests/hsc2hs/T10272.hsc b/testsuite/tests/hsc2hs/T10272.hsc
new file mode 100644
index 0000000000..c4ff6d180a
--- /dev/null
+++ b/testsuite/tests/hsc2hs/T10272.hsc
@@ -0,0 +1,6 @@
+module Main where
+
+#include "T10272.h"
+
+main :: IO ()
+main = print #{alignment eight}
diff --git a/testsuite/tests/hsc2hs/T10272.stdout b/testsuite/tests/hsc2hs/T10272.stdout
new file mode 100644
index 0000000000..45a4fb75db
--- /dev/null
+++ b/testsuite/tests/hsc2hs/T10272.stdout
@@ -0,0 +1 @@
+8
diff --git a/testsuite/tests/hsc2hs/T4340.hsc b/testsuite/tests/hsc2hs/T4340.hsc
new file mode 100644
index 0000000000..5ae9e2a3a9
--- /dev/null
+++ b/testsuite/tests/hsc2hs/T4340.hsc
@@ -0,0 +1,8 @@
+module Main where
+
+#include <stdint.h>
+
+#def typedef struct { uint8_t a; uint64_t b; uint16_t c; } eight;
+
+main :: IO ()
+main = print #{alignment eight}
diff --git a/testsuite/tests/hsc2hs/T4340.stdout b/testsuite/tests/hsc2hs/T4340.stdout
new file mode 100644
index 0000000000..45a4fb75db
--- /dev/null
+++ b/testsuite/tests/hsc2hs/T4340.stdout
@@ -0,0 +1 @@
+8
diff --git a/testsuite/tests/hsc2hs/all.T b/testsuite/tests/hsc2hs/all.T
index b0957911b6..d4fc69d88d 100644
--- a/testsuite/tests/hsc2hs/all.T
+++ b/testsuite/tests/hsc2hs/all.T
@@ -25,3 +25,13 @@ test('T3837',
      run_command,
      ['$MAKE -s --no-print-directory T3837'])
 
+test('T4340',
+     [extra_clean(['T4340.hs', 'T4340_hsc_make.c',
+                   'T4340_hsc.c', 'T4340_hsc.h'])],
+     run_command,
+     ['$MAKE -s --no-print-directory T4340'])
+
+test('T10272',
+     [extra_clean(['T10272.hs', 'T10272_hsc_make.c'])],
+     run_command,
+     ['$MAKE -s --no-print-directory T10272'])