builder: c/library: support passing --whole-archive on linking

When linking internal libs set have the "library/link-whole" attribute set
to true, linking them will cause "-Wl,--whole-archive" to be passed.

That's only desired in a few cases, eg. if the objects contain some
sections that aren't referred at link time, but loaded at runtime,
(eg. linked-in glib resource)

Signed-off-by: Enrico Weigelt, metux IT consult <[email protected]>

engine/builder/c/library.go

@@ -4,6 +4,7 @@ import (
 	"github.com/metux/go-metabuild/engine/builder/base"
 	"github.com/metux/go-metabuild/spec"
 	"github.com/metux/go-metabuild/spec/target"
+	"github.com/metux/go-metabuild/util"
 	"github.com/metux/go-metabuild/util/compiler"
 	"github.com/metux/go-metabuild/util/jobs"
 )
@@ -18,6 +19,7 @@ func (b *BuilderCLibrary) JobPrepare(id jobs.JobId) error {
 	libname := b.RequiredEntryStr(target.KeyLibraryName)
 	pkgname := b.RequiredEntryStr(target.KeyPkgName)
 	pkgid := b.RequiredEntryStr(target.KeyLibraryPkgId)
+	archive := "-l:" + b.RequiredEntryStr(target.KeyStaticLib)
 
 	cflags = []string{"-I."}
 
@@ -26,8 +28,10 @@ func (b *BuilderCLibrary) JobPrepare(id jobs.JobId) error {
 		PkgSpec:       pkgname,
 		SharedLdflags: []string{"-L.", "-l" + libname},
 		SharedCflags:  cflags,
-		StaticLdflags: []string{"-L.", "-l:" + b.RequiredEntryStr(target.KeyStaticLib)},
-		StaticCflags:  cflags,
+		StaticLdflags: util.ValIf(b.EntryBoolDef(target.KeyLibraryLinkWhole, false),
+			[]string{"-L.", "-Wl,--whole-archive", archive, "-Wl,--no-whole-archive"},
+			[]string{"-L.", archive}),
+		StaticCflags: cflags,
 	}
 
 	return b.BuildConf.SetPkgConfig(b.ForBuild(), pkgid, pi)

spec/target/keys.go

@@ -53,6 +53,9 @@ const (
 	KeyLibraryName    = Key("library/name")
 	KeyStaticLib      = Key("static::file")
 
+	// static / archives
+	KeyLibraryLinkWhole = Key("library/link-whole")
+
 	// library devlink
 	KeyLinkTarget = Key("target")
 )