[dev.link] cmd/link: panic if HeadType is not set

In the code there are conditions like !ctxt.IsDarwin(). This will
accidentally be true if HeadType is not yet set. Panic when
HeadType is not set, to catch errors.

Change-Id: Ic891123f27f0276fff5a4b5d29e5b1f7ebbb94ee
Reviewed-on: https://go-review.googlesource.com/c/go/+/229869
Run-TryBot: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

diff --git a/src/cmd/link/internal/ld/target.go b/src/cmd/link/internal/ld/target.go
index 7aa2c1ccd0c873359e1711ae9b3d9a0f0b33fa4f..8c07d77fd880222eb9d9abd015d7a07f5478d3bf 100644 (file)
--- a/src/cmd/link/internal/ld/target.go
+++ b/src/cmd/link/internal/ld/target.go
@@ -61,6 +61,7 @@ func (t *Target) CanUsePlugins() bool {
 }
 
 func (t *Target) IsElf() bool {
+       t.mustSetHeadType()
        return t.IsELF
 }
 
@@ -112,37 +113,51 @@ func (t *Target) IsWasm() bool {
 //
 
 func (t *Target) IsLinux() bool {
+       t.mustSetHeadType()
        return t.HeadType == objabi.Hlinux
 }
 
 func (t *Target) IsDarwin() bool {
+       t.mustSetHeadType()
        return t.HeadType == objabi.Hdarwin
 }
 
 func (t *Target) IsWindows() bool {
+       t.mustSetHeadType()
        return t.HeadType == objabi.Hwindows
 }
 
 func (t *Target) IsPlan9() bool {
+       t.mustSetHeadType()
        return t.HeadType == objabi.Hplan9
 }
 
 func (t *Target) IsAIX() bool {
+       t.mustSetHeadType()
        return t.HeadType == objabi.Haix
 }
 
 func (t *Target) IsSolaris() bool {
+       t.mustSetHeadType()
        return t.HeadType == objabi.Hsolaris
 }
 
 func (t *Target) IsNetbsd() bool {
+       t.mustSetHeadType()
        return t.HeadType == objabi.Hnetbsd
 }
 
 func (t *Target) IsOpenbsd() bool {
+       t.mustSetHeadType()
        return t.HeadType == objabi.Hopenbsd
 }
 
+func (t *Target) mustSetHeadType() {
+       if t.HeadType == objabi.Hunknown {
+               panic("HeadType is not set")
+       }
+}
+
 //
 // MISC
 //