std.Target: Move isLib{C,Cxx}LibName() to std.zig.target.

These are really answering questions about the Zig compiler's capacity to
provide a libc/libc++ implementation. As such, std.zig.target seems like a more
fitting place for these.

lib/std/Build/Module.zig

@@ -492,11 +492,11 @@ pub fn linkSystemLibrary(
     const b = m.owner;
 
     const target = m.requireKnownTarget();
-    if (target.isLibCLibName(name)) {
+    if (std.zig.target.isLibCLibName(target, name)) {
         m.link_libc = true;
         return;
     }
-    if (target.isLibCxxLibName(name)) {
+    if (std.zig.target.isLibCxxLibName(target, name)) {
         m.link_libcpp = true;
         return;
     }

lib/std/Build/Step/Compile.zig

@@ -611,11 +611,13 @@ pub fn dependsOnSystemLibrary(compile: *const Compile, name: []const u8) bool {
         is_linking_libcpp = is_linking_libcpp or module.link_libcpp == true;
     }
 
-    if (compile.rootModuleTarget().isLibCLibName(name)) {
+    const target = compile.rootModuleTarget();
+
+    if (std.zig.target.isLibCLibName(target, name)) {
         return is_linking_libc;
     }
 
-    if (compile.rootModuleTarget().isLibCxxLibName(name)) {
+    if (std.zig.target.isLibCxxLibName(target, name)) {
         return is_linking_libcpp;
     }
 

lib/std/Target.zig

@@ -2868,141 +2868,6 @@ pub fn cTypePreferredAlignment(target: Target, c_type: CType) u16 {
     );
 }
 
-pub fn isLibCLibName(target: std.Target, name: []const u8) bool {
-    const ignore_case = target.os.tag.isDarwin() or target.os.tag == .windows;
-
-    if (eqlIgnoreCase(ignore_case, name, "c"))
-        return true;
-
-    if (target.isMinGW()) {
-        if (eqlIgnoreCase(ignore_case, name, "m"))
-            return true;
-        if (eqlIgnoreCase(ignore_case, name, "mingw32"))
-            return true;
-        if (eqlIgnoreCase(ignore_case, name, "msvcrt-os"))
-            return true;
-        if (eqlIgnoreCase(ignore_case, name, "mingwex"))
-            return true;
-        if (eqlIgnoreCase(ignore_case, name, "uuid"))
-            return true;
-        if (eqlIgnoreCase(ignore_case, name, "bits"))
-            return true;
-        if (eqlIgnoreCase(ignore_case, name, "dmoguids"))
-            return true;
-        if (eqlIgnoreCase(ignore_case, name, "dxerr8"))
-            return true;
-        if (eqlIgnoreCase(ignore_case, name, "dxerr9"))
-            return true;
-        if (eqlIgnoreCase(ignore_case, name, "mfuuid"))
-            return true;
-        if (eqlIgnoreCase(ignore_case, name, "msxml2"))
-            return true;
-        if (eqlIgnoreCase(ignore_case, name, "msxml6"))
-            return true;
-        if (eqlIgnoreCase(ignore_case, name, "amstrmid"))
-            return true;
-        if (eqlIgnoreCase(ignore_case, name, "wbemuuid"))
-            return true;
-        if (eqlIgnoreCase(ignore_case, name, "wmcodecdspuuid"))
-            return true;
-        if (eqlIgnoreCase(ignore_case, name, "dxguid"))
-            return true;
-        if (eqlIgnoreCase(ignore_case, name, "ksguid"))
-            return true;
-        if (eqlIgnoreCase(ignore_case, name, "locationapi"))
-            return true;
-        if (eqlIgnoreCase(ignore_case, name, "portabledeviceguids"))
-            return true;
-        if (eqlIgnoreCase(ignore_case, name, "mfuuid"))
-            return true;
-        if (eqlIgnoreCase(ignore_case, name, "dloadhelper"))
-            return true;
-        if (eqlIgnoreCase(ignore_case, name, "strmiids"))
-            return true;
-        if (eqlIgnoreCase(ignore_case, name, "mfuuid"))
-            return true;
-        if (eqlIgnoreCase(ignore_case, name, "adsiid"))
-            return true;
-
-        return false;
-    }
-
-    if (target.abi.isGnu() or target.abi.isMusl()) {
-        if (eqlIgnoreCase(ignore_case, name, "m"))
-            return true;
-        if (eqlIgnoreCase(ignore_case, name, "rt"))
-            return true;
-        if (eqlIgnoreCase(ignore_case, name, "pthread"))
-            return true;
-        if (eqlIgnoreCase(ignore_case, name, "util"))
-            return true;
-        if (eqlIgnoreCase(ignore_case, name, "resolv"))
-            return true;
-        if (eqlIgnoreCase(ignore_case, name, "dl"))
-            return true;
-    }
-
-    if (target.abi.isMusl()) {
-        if (eqlIgnoreCase(ignore_case, name, "crypt"))
-            return true;
-        if (eqlIgnoreCase(ignore_case, name, "xnet"))
-            return true;
-    }
-
-    if (target.os.tag.isDarwin()) {
-        if (eqlIgnoreCase(ignore_case, name, "System"))
-            return true;
-        if (eqlIgnoreCase(ignore_case, name, "c"))
-            return true;
-        if (eqlIgnoreCase(ignore_case, name, "dbm"))
-            return true;
-        if (eqlIgnoreCase(ignore_case, name, "dl"))
-            return true;
-        if (eqlIgnoreCase(ignore_case, name, "info"))
-            return true;
-        if (eqlIgnoreCase(ignore_case, name, "m"))
-            return true;
-        if (eqlIgnoreCase(ignore_case, name, "poll"))
-            return true;
-        if (eqlIgnoreCase(ignore_case, name, "proc"))
-            return true;
-        if (eqlIgnoreCase(ignore_case, name, "pthread"))
-            return true;
-        if (eqlIgnoreCase(ignore_case, name, "rpcsvc"))
-            return true;
-    }
-
-    if (target.os.isAtLeast(.macos, .{ .major = 10, .minor = 8, .patch = 0 }) orelse false) {
-        if (eqlIgnoreCase(ignore_case, name, "mx"))
-            return true;
-    }
-
-    if (target.os.tag == .haiku) {
-        if (eqlIgnoreCase(ignore_case, name, "root"))
-            return true;
-        if (eqlIgnoreCase(ignore_case, name, "network"))
-            return true;
-    }
-
-    return false;
-}
-
-pub fn isLibCxxLibName(target: std.Target, name: []const u8) bool {
-    const ignore_case = target.os.tag.isDarwin() or target.os.tag == .windows;
-
-    return eqlIgnoreCase(ignore_case, name, "c++") or
-        eqlIgnoreCase(ignore_case, name, "stdc++") or
-        eqlIgnoreCase(ignore_case, name, "c++abi");
-}
-
-fn eqlIgnoreCase(ignore_case: bool, a: []const u8, b: []const u8) bool {
-    if (ignore_case) {
-        return std.ascii.eqlIgnoreCase(a, b);
-    } else {
-        return std.mem.eql(u8, a, b);
-    }
-}
-
 pub fn osArchName(target: std.Target) [:0]const u8 {
     return target.os.tag.archName(target.cpu.arch);
 }

lib/std/zig/target.zig

@@ -124,4 +124,139 @@ pub fn muslArchName(arch: std.Target.Cpu.Arch) [:0]const u8 {
     }
 }
 
+pub fn isLibCLibName(target: std.Target, name: []const u8) bool {
+    const ignore_case = target.os.tag.isDarwin() or target.os.tag == .windows;
+
+    if (eqlIgnoreCase(ignore_case, name, "c"))
+        return true;
+
+    if (target.isMinGW()) {
+        if (eqlIgnoreCase(ignore_case, name, "m"))
+            return true;
+        if (eqlIgnoreCase(ignore_case, name, "mingw32"))
+            return true;
+        if (eqlIgnoreCase(ignore_case, name, "msvcrt-os"))
+            return true;
+        if (eqlIgnoreCase(ignore_case, name, "mingwex"))
+            return true;
+        if (eqlIgnoreCase(ignore_case, name, "uuid"))
+            return true;
+        if (eqlIgnoreCase(ignore_case, name, "bits"))
+            return true;
+        if (eqlIgnoreCase(ignore_case, name, "dmoguids"))
+            return true;
+        if (eqlIgnoreCase(ignore_case, name, "dxerr8"))
+            return true;
+        if (eqlIgnoreCase(ignore_case, name, "dxerr9"))
+            return true;
+        if (eqlIgnoreCase(ignore_case, name, "mfuuid"))
+            return true;
+        if (eqlIgnoreCase(ignore_case, name, "msxml2"))
+            return true;
+        if (eqlIgnoreCase(ignore_case, name, "msxml6"))
+            return true;
+        if (eqlIgnoreCase(ignore_case, name, "amstrmid"))
+            return true;
+        if (eqlIgnoreCase(ignore_case, name, "wbemuuid"))
+            return true;
+        if (eqlIgnoreCase(ignore_case, name, "wmcodecdspuuid"))
+            return true;
+        if (eqlIgnoreCase(ignore_case, name, "dxguid"))
+            return true;
+        if (eqlIgnoreCase(ignore_case, name, "ksguid"))
+            return true;
+        if (eqlIgnoreCase(ignore_case, name, "locationapi"))
+            return true;
+        if (eqlIgnoreCase(ignore_case, name, "portabledeviceguids"))
+            return true;
+        if (eqlIgnoreCase(ignore_case, name, "mfuuid"))
+            return true;
+        if (eqlIgnoreCase(ignore_case, name, "dloadhelper"))
+            return true;
+        if (eqlIgnoreCase(ignore_case, name, "strmiids"))
+            return true;
+        if (eqlIgnoreCase(ignore_case, name, "mfuuid"))
+            return true;
+        if (eqlIgnoreCase(ignore_case, name, "adsiid"))
+            return true;
+
+        return false;
+    }
+
+    if (target.abi.isGnu() or target.abi.isMusl()) {
+        if (eqlIgnoreCase(ignore_case, name, "m"))
+            return true;
+        if (eqlIgnoreCase(ignore_case, name, "rt"))
+            return true;
+        if (eqlIgnoreCase(ignore_case, name, "pthread"))
+            return true;
+        if (eqlIgnoreCase(ignore_case, name, "util"))
+            return true;
+        if (eqlIgnoreCase(ignore_case, name, "resolv"))
+            return true;
+        if (eqlIgnoreCase(ignore_case, name, "dl"))
+            return true;
+    }
+
+    if (target.abi.isMusl()) {
+        if (eqlIgnoreCase(ignore_case, name, "crypt"))
+            return true;
+        if (eqlIgnoreCase(ignore_case, name, "xnet"))
+            return true;
+    }
+
+    if (target.os.tag.isDarwin()) {
+        if (eqlIgnoreCase(ignore_case, name, "System"))
+            return true;
+        if (eqlIgnoreCase(ignore_case, name, "c"))
+            return true;
+        if (eqlIgnoreCase(ignore_case, name, "dbm"))
+            return true;
+        if (eqlIgnoreCase(ignore_case, name, "dl"))
+            return true;
+        if (eqlIgnoreCase(ignore_case, name, "info"))
+            return true;
+        if (eqlIgnoreCase(ignore_case, name, "m"))
+            return true;
+        if (eqlIgnoreCase(ignore_case, name, "poll"))
+            return true;
+        if (eqlIgnoreCase(ignore_case, name, "proc"))
+            return true;
+        if (eqlIgnoreCase(ignore_case, name, "pthread"))
+            return true;
+        if (eqlIgnoreCase(ignore_case, name, "rpcsvc"))
+            return true;
+    }
+
+    if (target.os.isAtLeast(.macos, .{ .major = 10, .minor = 8, .patch = 0 }) orelse false) {
+        if (eqlIgnoreCase(ignore_case, name, "mx"))
+            return true;
+    }
+
+    if (target.os.tag == .haiku) {
+        if (eqlIgnoreCase(ignore_case, name, "root"))
+            return true;
+        if (eqlIgnoreCase(ignore_case, name, "network"))
+            return true;
+    }
+
+    return false;
+}
+
+pub fn isLibCxxLibName(target: std.Target, name: []const u8) bool {
+    const ignore_case = target.os.tag.isDarwin() or target.os.tag == .windows;
+
+    return eqlIgnoreCase(ignore_case, name, "c++") or
+        eqlIgnoreCase(ignore_case, name, "stdc++") or
+        eqlIgnoreCase(ignore_case, name, "c++abi");
+}
+
+fn eqlIgnoreCase(ignore_case: bool, a: []const u8, b: []const u8) bool {
+    if (ignore_case) {
+        return std.ascii.eqlIgnoreCase(a, b);
+    } else {
+        return std.mem.eql(u8, a, b);
+    }
+}
+
 const std = @import("std");

src/Sema.zig

@@ -9606,7 +9606,7 @@ fn handleExternLibName(
         const comp = zcu.comp;
         const target = zcu.getTarget();
         log.debug("extern fn symbol expected in lib '{s}'", .{lib_name});
-        if (target.isLibCLibName(lib_name)) {
+        if (std.zig.target.isLibCLibName(target, lib_name)) {
             if (!comp.config.link_libc) {
                 return sema.fail(
                     block,
@@ -9617,7 +9617,7 @@ fn handleExternLibName(
             }
             break :blk;
         }
-        if (target.isLibCxxLibName(lib_name)) {
+        if (std.zig.target.isLibCxxLibName(target, lib_name)) {
             if (!comp.config.link_libcpp) return sema.fail(
                 block,
                 src_loc,

src/main.zig

@@ -3765,11 +3765,11 @@ fn createModule(
             info: SystemLib,
         }) = .{};
         for (create_module.system_libs.keys(), create_module.system_libs.values()) |lib_name, info| {
-            if (target.isLibCLibName(lib_name)) {
+            if (std.zig.target.isLibCLibName(target, lib_name)) {
                 create_module.opts.link_libc = true;
                 continue;
             }
-            if (target.isLibCxxLibName(lib_name)) {
+            if (std.zig.target.isLibCxxLibName(target, lib_name)) {
                 create_module.opts.link_libcpp = true;
                 continue;
             }