From 79ea839b635d1fd84b6ce8a47e086f01d64198e6 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Tiziano=20M=C3=BCller?= <tiziano.mueller@chem.uzh.ch>
Date: Sat, 6 Oct 2018 14:10:02 +0200
Subject: [PATCH] fix parallel build issues with APFS/HFS+/ext2/3 in
 netlib-lapack

The problem is that OpenBLAS sets the LAPACKE_LIB and the TMGLIB to the
same object and uses the `ar` feature to update the archive file. If the
underlying filesystem does not have sub-second timestamp resolution and
the system is fast enough (or `ccache` is used), the timestamp of the
builds which should be added to the previously generated archive is the
same as the archive file itself and therefore `make` does not update the
archive.

Since OpenBLAS takes care to not run the different targets updating the
archive in parallel, the easiest solution is to declare the respective
targets `.PHONY`, forcing `make` to always update them.

fixes #1682
---
 lapack-netlib/LAPACKE/src/Makefile    | 2 ++
 lapack-netlib/SRC/Makefile            | 2 ++
 lapack-netlib/TESTING/MATGEN/Makefile | 2 ++
 3 files changed, 6 insertions(+)

diff --git a/lapack-netlib/LAPACKE/src/Makefile b/lapack-netlib/LAPACKE/src/Makefile
index 44884d4a5..7672f9f73 100644
--- a/lapack-netlib/LAPACKE/src/Makefile
+++ b/lapack-netlib/LAPACKE/src/Makefile
@@ -2454,6 +2454,8 @@ endif
 
 all: ../../$(LAPACKELIB)
 
+.PHONY: ../../$(LAPACKELIB)
+
 ../../$(LAPACKELIB): $(OBJ_A) $(OBJ_B) $(DEPRECATED) $(EXTENDED) $(MATGEN)
 	$(ARCH) $(ARCHFLAGS) $@ $(OBJ_A)
 	$(ARCH) $(ARCHFLAGS) $@ $(OBJ_B)
diff --git a/lapack-netlib/SRC/Makefile b/lapack-netlib/SRC/Makefile
index 531cb51fc..87a8f51e4 100644
--- a/lapack-netlib/SRC/Makefile
+++ b/lapack-netlib/SRC/Makefile
@@ -552,6 +552,8 @@ endif
 
 all: ../$(LAPACKLIB)
 
+.PHONY: ../$(LAPACKLIB)
+
 ../$(LAPACKLIB): $(ALLOBJ) $(ALLXOBJ) $(DEPRECATED)
 	$(ARCH) $(ARCHFLAGS) $@ $(ALLOBJ) $(ALLXOBJ) $(DEPRECATED)
 	$(RANLIB) $@
diff --git a/lapack-netlib/TESTING/MATGEN/Makefile b/lapack-netlib/TESTING/MATGEN/Makefile
index e20004c2f..a1d784fa5 100644
--- a/lapack-netlib/TESTING/MATGEN/Makefile
+++ b/lapack-netlib/TESTING/MATGEN/Makefile
@@ -57,6 +57,8 @@ all: ../../$(TMGLIB)
 ALLOBJ = $(SMATGEN) $(CMATGEN) $(SCATGEN) $(DMATGEN) $(ZMATGEN) \
 	$(DZATGEN)
 
+.PHONY: ../../$(TMGLIB)
+
 ../../$(TMGLIB): $(ALLOBJ)
 	$(ARCH) $(ARCHFLAGS) $@ $^
 	$(RANLIB) $@