GHC doesn't handle ./ prefixed paths correctly (#12674)

Summary: If a filename starts with a hypen, GHC keeps the prefixed "./" path.

Test Plan: make test TEST=T12674

Reviewers: Phyx, nomeata, bgamari, erikd

Reviewed By: Phyx

Subscribers: rwbarton, thomie, carter

GHC Trac Issues: #12674

Differential Revision: https://phabricator.haskell.org/D5009

5 files changed, 23 insertions, 0 deletions

diff --git a/testsuite/tests/driver/T12674/-T12674.hs b/testsuite/tests/driver/T12674/-T12674.hs
new file mode 100644
index 0000000000..11a7c546bd
--- /dev/null
+++ b/testsuite/tests/driver/T12674/-T12674.hs
@@ -0,0 +1,10 @@
+{-# LANGUAGE ForeignFunctionInterface, CPP #-}
+import Foreign.C
+foreign import ccall unsafe "test" test :: CInt -> IO ()
+
+main :: IO ()
+-- Use conditional language to test passing a file with a filename
+-- starting with a hyphen to the preprocessor.
+#if defined(__GLASGOW_HASKELL__)
+main = test 3
+#endif
diff --git a/testsuite/tests/driver/T12674/-T12674c.c b/testsuite/tests/driver/T12674/-T12674c.c
new file mode 100644
index 0000000000..3b38c5879e
--- /dev/null
+++ b/testsuite/tests/driver/T12674/-T12674c.c
@@ -0,0 +1,6 @@
+#include <stdio.h>
+void test(int arg
+)
+{
+   printf("Result %i\n", arg );
+}
diff --git a/testsuite/tests/driver/T12674/T12674.stdout b/testsuite/tests/driver/T12674/T12674.stdout
new file mode 100644
index 0000000000..76239dd5cb
--- /dev/null
+++ b/testsuite/tests/driver/T12674/T12674.stdout
@@ -0,0 +1 @@
+Result 3
diff --git a/testsuite/tests/driver/T12674/T12674w.stdout b/testsuite/tests/driver/T12674/T12674w.stdout
new file mode 100644
index 0000000000..76239dd5cb
--- /dev/null
+++ b/testsuite/tests/driver/T12674/T12674w.stdout
@@ -0,0 +1 @@
+Result 3
diff --git a/testsuite/tests/driver/T12674/all.T b/testsuite/tests/driver/T12674/all.T
new file mode 100644
index 0000000000..0f9e205c9f
--- /dev/null
+++ b/testsuite/tests/driver/T12674/all.T
@@ -0,0 +1,5 @@
+test('T12674', [extra_files(['-T12674.hs', '-T12674c.c'])],
+                multi_compile, ['./-T12674.hs', [('././-T12674c.c', '')], '-v0'])
+test('T12674w', [extra_files(['-T12674.hs', '-T12674c.c']),
+                unless(opsys('mingw32'), skip)],
+                multi_compile, ['.\\\-T12674.hs', [('.\\\.\\\-T12674c.c', '')], '-v0'])