sys/targets: ignore unachievable test targets

Don't set BuildOS for those targets, where we have not managed to find a
reference target based on GOARCH/GOOS. It doesn't make much sense to use
such test targets in such cases.

1 files changed, 28 insertions, 26 deletions

diff --git a/sys/targets/targets.go b/sys/targets/targets.go
index ba84b1ee0..7d10dfc04 100644
--- a/sys/targets/targets.go
+++ b/sys/targets/targets.go
@@ -625,34 +625,36 @@ func init() {
 		goos = Linux
 	}
 	for _, target := range List[TestOS] {
-		if List[goos] != nil {
-			arch := arch64
-			if target.PtrSize == 4 {
-				arch = arch32
-			}
-			host := List[goos][arch]
-			if host != nil {
-				target.CCompiler = host.CCompiler
-				target.CPP = host.CPP
-				target.CFlags = append(append([]string{}, host.CFlags...), target.CFlags...)
-				target.CFlags = processMergedFlags(target.CFlags)
-				// In ESA/390 mode, the CPU is able to address only 31bit of memory but
-				// arithmetic operations are still 32bit
-				// Fix cflags by replacing compiler's -m32 option with -m31
-				if arch == S390x {
-					for i := range target.CFlags {
-						target.CFlags[i] = strings.Replace(target.CFlags[i], "-m32", "-m31", -1)
-					}
-				}
-			}
-			if target.PtrSize == 4 && goos == FreeBSD && arch == AMD64 {
-				// A hack to let 32-bit "test" target tests run on FreeBSD:
-				// freebsd/386 requires a non-default DataOffset to avoid
-				// clobbering mappings created by the C runtime. Since that is the
-				// only target with this constraint, just special-case it for now.
-				target.DataOffset = List[goos][I386].DataOffset
+		if List[goos] == nil {
+			continue
+		}
+		arch := arch64
+		if target.PtrSize == 4 {
+			arch = arch32
+		}
+		host := List[goos][arch]
+		if host == nil {
+			continue
+		}
+		target.CCompiler = host.CCompiler
+		target.CPP = host.CPP
+		target.CFlags = append(append([]string{}, host.CFlags...), target.CFlags...)
+		target.CFlags = processMergedFlags(target.CFlags)
+		// In ESA/390 mode, the CPU is able to address only 31bit of memory but
+		// arithmetic operations are still 32bit
+		// Fix cflags by replacing compiler's -m32 option with -m31
+		if arch == S390x {
+			for i := range target.CFlags {
+				target.CFlags[i] = strings.Replace(target.CFlags[i], "-m32", "-m31", -1)
 			}
 		}
+		if target.PtrSize == 4 && goos == FreeBSD && arch == AMD64 {
+			// A hack to let 32-bit "test" target tests run on FreeBSD:
+			// freebsd/386 requires a non-default DataOffset to avoid
+			// clobbering mappings created by the C runtime. Since that is the
+			// only target with this constraint, just special-case it for now.
+			target.DataOffset = List[goos][I386].DataOffset
+		}
 		target.BuildOS = goos
 	}
 }