Merge pull request #1350 from tweag/cc-wrapper

Fix issues around cc_wrapper with Cabal builds

Author: mergify[bot]

haskell/private/cabal_wrapper.py.tpl

@@ -121,10 +121,16 @@ def tmpdir():
     # Executables are placed into `<distdir>/build/<package-name>/<binary>`.
     # Libraries are placed into `<distdir>/build/<library>`. I.e. there is an
     # extra subdirectory for libraries.
-    if component.startswith("exe:"):
-        distdir = tempfile.mkdtemp(dir=os.path.dirname(os.path.dirname(pkgroot)))
+    #
+    # On Windows we don't do dynamic linking and prefer shorter paths to avoid
+    # exceeding `MAX_PATH`.
+    if "%{is_windows}" == "True":
+        distdir = tempfile.mkdtemp()
     else:
-        distdir = tempfile.mkdtemp(dir=os.path.dirname(pkgroot))
+        if component.startswith("exe:"):
+            distdir = tempfile.mkdtemp(dir=os.path.dirname(os.path.dirname(pkgroot)))
+        else:
+            distdir = tempfile.mkdtemp(dir=os.path.dirname(pkgroot))
     try:
         yield distdir
     finally:
@@ -140,6 +146,7 @@ with tmpdir() as distdir:
     # absolute ones before doing so (using $execroot).
     old_cwd = os.getcwd()
     os.chdir(srcdir)
+    os.putenv("RULES_HASKELL_EXEC_ROOT", old_cwd)
     os.putenv("HOME", "/var/empty")
     os.putenv("TMPDIR", os.path.join(distdir, "tmp"))
     os.putenv("TMP", os.path.join(distdir, "tmp"))
@@ -165,7 +172,7 @@ with tmpdir() as distdir:
         # absolute paths refer the temporary directory that GHC uses for
         # intermediate template Haskell outputs. `cc_wrapper` should improved
         # in that regard.
-        "--builddir=" + os.path.relpath(distdir), \
+        "--builddir=" + (os.path.relpath(distdir) if "%{is_windows}" != "True" else distdir), \
         "--prefix=" + pkgroot, \
         "--libdir=" + libdir, \
         "--dynlibdir=" + dynlibdir, \

haskell/private/cc_wrapper.py.tpl

@@ -711,17 +711,17 @@ def find_solib_rpath(rpaths, output):
     """
     for rpath in rpaths:
         components = rpath.replace("\\", "/").split("/")
-        solib_rpath = []
+        solib_rpath = ""
         for comp in components:
-            solib_rpath.append(comp)
-            if comp.startswith("_solib_"):
-                return "/".join(solib_rpath)
+            solib_rpath = os.path.join(solib_rpath, comp)
+            if comp.startswith("_solib_") and os.path.isdir(resolve_rpath(solib_rpath, output)[1]):
+                return solib_rpath
 
     if is_temporary_output(output):
         # GHC generates temporary libraries outside the execroot. In that case
         # the Bazel generated RPATHs are not forwarded, and the solib directory
         # is not visible on the command-line.
-        for (root, dirnames, _) in breadth_first_walk("."):
+        for (root, dirnames, _) in breadth_first_walk(os.environ.get("RULES_HASKELL_EXEC_ROOT", ".")):
             if "_solib_{:cpu:}" in dirnames:
                 return os.path.join(root, "_solib_{:cpu:}")