From: Jeremy Kerr <jk@codeconstruct.com.au>
Date: Thu, 1 Jul 2021 06:26:57 +0000 (+0800)
Subject: Separate libs from link flags to fix link-order compile failure
X-Git-Tag: v1.0-rc0~114^2~2
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=0f8265b11cae3a4e7e71146ae7c6836ec2d9a632;p=users%2Fsagi%2Flibnvme.git

Separate libs from link flags to fix link-order compile failure

Currently, builds fail for me with a link error:

  /usr/bin/ld: ../src//libnvme.a(tree.ol): in function `nvme_ns_get_uuid':
  src/nvme/tree.c:1321: undefined reference to `uuid_copy'
  /usr/bin/ld: ../src//libnvme.a(json.ol): in function `json_read_config':
  src/nvme/json.c:152: undefined reference to `json_object_from_file'

Turns out my linker ("GNU ld (GNU Binutils for Debian) 2.35.2") is
sensitive to object argument order - the dependent libs need to be listed
last.

This change splits the required libraries into a LIBS variable, used
last on the Makefile rules to perform the link.

Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
---

diff --git a/configure b/configure
index c81f48ea..91a56d05 100755
--- a/configure
+++ b/configure
@@ -228,16 +228,16 @@ print_config "cpp" "${cpp}"
 
 if test "$libuuid" = "yes"; then
   output_sym "CONFIG_LIBUUID"
-  echo "override LDFLAGS += -luuid" >> $config_host_mak
+  echo "override LIBS += -luuid" >> $config_host_mak
   echo "override LIB_DEPENDS += uuid" >> $config_host_mak 
 fi
 if test "$systemd" = "yes"; then
   output_sym "CONFIG_SYSTEMD"
-  echo "override LDFLAGS += -lsystemd" >> $config_host_mak
+  echo "override LIBS += -lsystemd" >> $config_host_mak
 fi
 if test "$libjsonc" = "yes"; then
     output_sym "CONFIG_JSONC"
-    echo "override LDFLAGS += -ljson-c" >> $config_host_mak
+    echo "override LIBS += -ljson-c" >> $config_host_mak
     echo "override LIB_DEPENDS += json-c" >> $config_host_mak
 fi
 if test "$cpp" = "yes"; then
diff --git a/examples/Makefile b/examples/Makefile
index 24f85746..c909c87e 100644
--- a/examples/Makefile
+++ b/examples/Makefile
@@ -12,7 +12,7 @@ all_targets += telemetry-listen display-tree display-columnar discover-loop
 all: $(all_targets)
 
 %: %.c
-	$(QUIET_CC)$(CC) $(CFLAGS) -o $@ $< -lnvme ${LDFLAGS}
+	$(QUIET_CC)$(CC) $(CFLAGS) $(LDFLAGS) -o $@ $< -lnvme $(LIBS)
 
 clean:
 	rm -f $(all_targets)
diff --git a/src/Makefile b/src/Makefile
index a4c33dab..b706a6da 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -72,7 +72,7 @@ libnvme.a: $(libnvme_objs) $(libccan_objs)
 	$(QUIET_RANLIB)$(RANLIB) libnvme.a
 
 $(libname): $(libnvme_sobjs) $(libccan_sobjs) libnvme.map
-	$(QUIET_CC)$(CC) $(SO_CFLAGS) -Wl,--version-script=libnvme.map -Wl,-soname=$(soname) -o $@ $(libnvme_sobjs) $(libccan_sobjs) $(LINK_FLAGS)
+	$(QUIET_CC)$(CC) $(SO_CFLAGS) -Wl,--version-script=libnvme.map -Wl,-soname=$(soname) -o $@ $(libnvme_sobjs) $(libccan_sobjs) $(LINK_FLAGS) $(LIBS)
 
 install: $(all_targets)
 	$(INSTALL) -D -m 644 libnvme.a $(libdir)/libnvme.a
diff --git a/test/Makefile b/test/Makefile
index ed050d0b..2df695e0 100644
--- a/test/Makefile
+++ b/test/Makefile
@@ -23,10 +23,10 @@ all: $(all_targets)
 CXXFLAGS ?= -lstdc++
 
 %: %.cc
-	$(QUIET_CC)$(CC) $(CFLAGS) $(LDFLAGS) $(CXXFLAGS) -o $@ $< -lnvme
+	$(QUIET_CC)$(CC) $(CFLAGS) $(LDFLAGS) $(CXXFLAGS) -o $@ $< -lnvme $(LIBS)
 
 %: %.c
-	$(QUIET_CC)$(CC) $(CFLAGS) $(LDFLAGS) -o $@ $< -lnvme
+	$(QUIET_CC)$(CC) $(CFLAGS) $(LDFLAGS) -o $@ $< -lnvme $(LIBS)
 
 clean:
 	rm -f $(all_targets)