1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
|
From f1f1ae369a4cefd3474b3528e8d1847b18750605 Mon Sep 17 00:00:00 2001
From: Christian Marangi <ansuelsmth@gmail.com>
Date: Sat, 6 Apr 2024 14:41:54 +0200
Subject: [PATCH] Provide variant pkg-config file for multi-threaded static lib
Multi-threaded static library require -pthread to correctly link and works.
The pkg-config we provide tho only works with dynamic multi-threaded library
and won't provide the correct libs and cflags values if lib-mt is used.
To handle this, introduce an env variable MT to permit advanced user to
install and generate a correct pkg-config file for lib-mt or detect if
lib-mt target is called.
With MT env set on calling make install-pc, libzstd.pc.in is a
pkg-config file for a multi-threaded static library.
On calling make lib-mt, a libzstd.pc is generated for a multi-threaded
static library as it's what asked by the user by forcing it.
libzstd.pc is changed to PHONY to force regeneration of it on calling
lib targets or install-pc to handle case where the same directory is
used for mixed compilation.
This was notice while migrating from meson to make build system where
meson generates a correct .pc file while make doesn't.
Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
---
lib/Makefile | 20 +++++++++++++++++++-
lib/README.md | 4 ++++
lib/libzstd.pc.in | 4 ++--
3 files changed, 25 insertions(+), 3 deletions(-)
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -63,6 +63,8 @@ CPPFLAGS_DYNLIB += -DZSTD_MULTITHREAD #
LDFLAGS_DYNLIB += -pthread
CPPFLAGS_STATICLIB += # static library build defaults to single-threaded
+# pkg-config Libs.private points to LDFLAGS_DYNLIB
+PCLIB := $(LDFLAGS_DYNLIB)
ifeq ($(findstring GCC,$(CCVER)),GCC)
decompress/zstd_decompress_block.o : CFLAGS+=-fno-tree-vectorize
@@ -186,12 +188,15 @@ lib : libzstd.a libzstd
%-mt : CPPFLAGS_DYNLIB := -DZSTD_MULTITHREAD
%-mt : CPPFLAGS_STATICLIB := -DZSTD_MULTITHREAD
%-mt : LDFLAGS_DYNLIB := -pthread
+%-mt : PCLIB :=
+%-mt : PCMTLIB := $(LDFLAGS_DYNLIB)
%-mt : %
@echo multi-threaded build completed
%-nomt : CPPFLAGS_DYNLIB :=
%-nomt : LDFLAGS_DYNLIB :=
%-nomt : CPPFLAGS_STATICLIB :=
+%-nomt : PCLIB :=
%-nomt : %
@echo single-threaded build completed
@@ -292,6 +297,14 @@ PCLIBPREFIX := $(if $(findstring $(LIBDI
# to PREFIX, rather than as a resolved value.
PCEXEC_PREFIX := $(if $(HAS_EXPLICIT_EXEC_PREFIX),$(EXEC_PREFIX),$${prefix})
+
+ifneq ($(MT),)
+ PCLIB :=
+ PCMTLIB := $(LDFLAGS_DYNLIB)
+else
+ PCLIB := $(LDFLAGS_DYNLIB)
+endif
+
ifneq (,$(filter $(UNAME),FreeBSD NetBSD DragonFly))
PKGCONFIGDIR ?= $(PREFIX)/libdata/pkgconfig
else
@@ -308,6 +321,10 @@ INSTALL_PROGRAM ?= $(INSTALL)
INSTALL_DATA ?= $(INSTALL) -m 644
+# pkg-config library define.
+# For static single-threaded library declare -pthread in Libs.private
+# For static multi-threaded library declare -pthread in Libs and Cflags
+.PHONY: libzstd.pc
libzstd.pc: libzstd.pc.in
@echo creating pkgconfig
@sed \
@@ -316,7 +333,8 @@ libzstd.pc: libzstd.pc.in
-e 's|@INCLUDEDIR@|$(PCINCPREFIX)$(PCINCDIR)|' \
-e 's|@LIBDIR@|$(PCLIBPREFIX)$(PCLIBDIR)|' \
-e 's|@VERSION@|$(VERSION)|' \
- -e 's|@LIBS_PRIVATE@|$(LDFLAGS_DYNLIB)|' \
+ -e 's|@LIBS_MT@|$(PCMTLIB)|' \
+ -e 's|@LIBS_PRIVATE@|$(PCLIB)|' \
$< >$@
.PHONY: install
--- a/lib/README.md
+++ b/lib/README.md
@@ -27,12 +27,16 @@ Enabling multithreading requires 2 condi
For convenience, we provide a build target to generate multi and single threaded libraries:
- Force enable multithreading on both dynamic and static libraries by appending `-mt` to the target, e.g. `make lib-mt`.
+ Note that the `.pc` generated on calling `make lib-mt` will already include the require Libs and Cflags.
- Force disable multithreading on both dynamic and static libraries by appending `-nomt` to the target, e.g. `make lib-nomt`.
- By default, as mentioned before, dynamic library is multithreaded, and static library is single-threaded, e.g. `make lib`.
When linking a POSIX program with a multithreaded version of `libzstd`,
note that it's necessary to invoke the `-pthread` flag during link stage.
+The `.pc` generated from `make install` or `make install-pc` always assume a single-threaded static library
+is compiled. To correctly generate a `.pc` for the multi-threaded static library, set `MT=1` as ENV variable.
+
Multithreading capabilities are exposed
via the [advanced API defined in `lib/zstd.h`](https://github.com/facebook/zstd/blob/v1.4.3/lib/zstd.h#L351).
--- a/lib/libzstd.pc.in
+++ b/lib/libzstd.pc.in
@@ -11,6 +11,6 @@ Name: zstd
Description: fast lossless compression algorithm library
URL: https://facebook.github.io/zstd/
Version: @VERSION@
-Libs: -L${libdir} -lzstd
+Libs: -L${libdir} -lzstd @LIBS_MT@
Libs.private: @LIBS_PRIVATE@
-Cflags: -I${includedir}
+Cflags: -I${includedir} @LIBS_MT@
|