internal/rosa/cmake: implicit CMAKE_BUILD_TYPE

Lack of this behaviour is a holdover from when the helper was first split from the (now removed) LLVM helper.

Signed-off-by: Ophestra <cat@gensokyo.uk>

internal/rosa/cmake.go

@@ -122,6 +122,8 @@ type CMakeHelper struct {
 	// Path elements joined with source.
 	Append []string
 
+	// Value of CMAKE_BUILD_TYPE. The zero value is equivalent to "Release".
+	BuildType string
 	// CMake CACHE entries.
 	Cache []KV
 	// Runs after install.
@@ -164,14 +166,7 @@ func (*CMakeHelper) wantsDir() string { return "/cure/" }
 // script generates the cure script.
 func (attr *CMakeHelper) script(name string) string {
 	if attr == nil {
-		attr = &CMakeHelper{
-			Cache: []KV{
-				{"CMAKE_BUILD_TYPE", "Release"},
-			},
-		}
-	}
-	if len(attr.Cache) == 0 {
-		panic("CACHE must be non-empty")
+		attr = new(CMakeHelper)
 	}
 
 	generate := "Ninja"
@@ -189,6 +184,13 @@ func (attr *CMakeHelper) script(name string) string {
 		script += "\n" + test
 	}
 
+	cache := make([]KV, 1, 1+len(attr.Cache))
+	cache[0] = KV{"CMAKE_BUILD_TYPE", "Release"}
+	if attr.BuildType != "" {
+		cache[0][1] = attr.BuildType
+	}
+	cache = append(cache, attr.Cache...)
+
 	return `
 cmake -G ` + generate + ` \
 	-DCMAKE_C_COMPILER_TARGET="${ROSA_TRIPLE}" \
@@ -196,7 +198,7 @@ cmake -G ` + generate + ` \
 	-DCMAKE_ASM_COMPILER_TARGET="${ROSA_TRIPLE}" \
 	-DCMAKE_INSTALL_LIBDIR=lib \
 	` + strings.Join(slices.Collect(func(yield func(string) bool) {
-		for _, v := range attr.Cache {
+		for _, v := range cache {
 			if !yield("-D" + v[0] + "=" + v[1]) {
 				return
 			}