1From 65b79161b9e2848a174d3519a03348884f182975 Mon Sep 17 00:00:00 2001
2From: Khem Raj <raj.khem@gmail.com>
3Date: Wed, 18 Mar 2015 00:49:28 +0000
4Subject: [PATCH] eglibc: Help bootstrap cross toolchain
5
6Taken from EGLIBC, r1484 + r1525
7
8        2007-02-20  Jim Blandy  <jimb@codesourcery.com>
9
10                * Makefile (install-headers): Preserve old behavior: depend on
11                $(inst_includedir)/gnu/stubs.h only if install-bootstrap-headers
12                is set; otherwise, place gnu/stubs.h on the 'install-others' list.
13
14        2007-02-16  Jim Blandy  <jimb@codesourcery.com>
15
16                * Makefile: Amend make install-headers to install everything
17                necessary for building a cross-compiler.  Install gnu/stubs.h as
18                part of 'install-headers', not 'install-others'.
19                If install-bootstrap-headers is 'yes', install a dummy copy of
20                gnu/stubs.h, instead of computing the real thing.
21                * include/stubs-bootstrap.h: New file.
22
23Upstream-Status: Pending
24Signed-off-by: Khem Raj <raj.khem@gmail.com>
25---
26 Makefile                  | 22 +++++++++++++++++++++-
27 include/stubs-bootstrap.h | 12 ++++++++++++
28 2 files changed, 33 insertions(+), 1 deletion(-)
29 create mode 100644 include/stubs-bootstrap.h
30
31diff --git a/Makefile b/Makefile
32index 7052b46df8..46073abaa8 100644
33--- a/Makefile
34+++ b/Makefile
35@@ -79,9 +79,18 @@ subdir-dirs = include
36 vpath %.h $(subdir-dirs)
37
38 # What to install.
39-install-others = $(inst_includedir)/gnu/stubs.h
40 install-bin-script =
41
42+# If we're bootstrapping, install a dummy gnu/stubs.h along with the
43+# other headers, so 'make install-headers' produces a useable include
44+# tree.  Otherwise, install gnu/stubs.h later, after the rest of the
45+# build is done.
46+ifeq ($(install-bootstrap-headers),yes)
47+install-headers: $(inst_includedir)/gnu/stubs.h
48+else
49+install-others = $(inst_includedir)/gnu/stubs.h
50+endif
51+
52 ifeq (yes,$(build-shared))
53 headers += gnu/lib-names.h
54 endif
55@@ -421,6 +430,16 @@ others: $(common-objpfx)testrun.sh $(common-objpfx)debugglibc.sh
56
57 subdir-stubs := $(foreach dir,$(subdirs),$(common-objpfx)$(dir)/stubs)
58
59+# gnu/stubs.h depends (via the subdir 'stubs' targets) on all the .o
60+# files in EGLIBC.  For bootstrapping a GCC/EGLIBC pair, an empty
61+# gnu/stubs.h is good enough.
62+ifeq ($(install-bootstrap-headers),yes)
63+$(inst_includedir)/gnu/stubs.h: include/stubs-bootstrap.h $(+force)
64+	$(make-target-directory)
65+	$(INSTALL_DATA) $< $@
66+
67+installed-stubs =
68+else
69 ifndef abi-variants
70 installed-stubs = $(inst_includedir)/gnu/stubs.h
71 else
72@@ -447,6 +466,7 @@ $(inst_includedir)/gnu/stubs.h: $(+force)
73
74 install-others-nosubdir: $(installed-stubs)
75 endif
76+endif
77
78
79 # Since stubs.h is never needed when building the library, we simplify the
80diff --git a/include/stubs-bootstrap.h b/include/stubs-bootstrap.h
81new file mode 100644
82index 0000000000..1d2b669aff
83--- /dev/null
84+++ b/include/stubs-bootstrap.h
85@@ -0,0 +1,12 @@
86+/* Placeholder stubs.h file for bootstrapping.
87+
88+   When bootstrapping a GCC/EGLIBC pair, GCC requires that the EGLIBC
89+   headers be installed, but we can't fully build EGLIBC without that
90+   GCC.  So we run the command:
91+
92+      make install-headers install-bootstrap-headers=yes
93+
94+   to install the headers GCC needs, but avoid building certain
95+   difficult headers.  The <gnu/stubs.h> header depends, via the
96+   EGLIBC subdir 'stubs' make targets, on every .o file in EGLIBC, but
97+   an empty stubs.h like this will do fine for GCC.  */
98