Add betterC probing for performance and for applications without drun…

…time
dlang · Dec 24, 2023 · 8742ca1 · 8742ca1
1 parent a86d81c
commit 8742ca1
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Showing 2 changed files with 46 additions and 19 deletions.
diff --git a/source/dub/compilers/compiler.d b/source/dub/compilers/compiler.d
@@ -183,18 +183,32 @@ interface Compiler {
 		import dub.compilers.utils : generatePlatformProbeFile, readPlatformJsonProbe;
 		import std.string : format, strip;
 
-		auto fil = generatePlatformProbeFile();
+		NativePath fil = generatePlatformProbeFile!true();
+		auto result_betterC = execute(compiler_binary ~ args ~ "-betterC" ~ fil.toNativeString());
+		// expect a result <>0 for a betterC probe
+		BuildPlatform build_platform;
+		string ver;
+		bool retry;
+		try {
+			build_platform = readPlatformJsonProbe(result_betterC.output);
+			ver = determineVersion(compiler_binary, result_betterC.output).strip;
+		} catch(Exception e) {
+			logWarn(`Could not probe this compiler using betterC, reverting to druntime probe.`);
+			retry = true;
+		}
+		if (retry) {
+			fil = generatePlatformProbeFile!false();
 
-		auto result = execute(compiler_binary ~ args ~ fil.toNativeString());
-		enforce!CompilerInvocationException(result.status == 0,
-				format("Failed to invoke the compiler %s to determine the build platform: %s",
-				compiler_binary, result.output));
+			auto result = execute(compiler_binary ~ args ~ fil.toNativeString());
+			enforce!CompilerInvocationException(result.status == 0,
+					format("Failed to invoke the compiler %s to determine the build platform: %s",
+					compiler_binary, result.output));
 
-		auto build_platform = readPlatformJsonProbe(result.output);
+			build_platform = readPlatformJsonProbe(result.output);
+			ver = determineVersion(compiler_binary, result.output).strip;
+		}
 		build_platform.compilerBinary = compiler_binary;
 
-		auto ver = determineVersion(compiler_binary, result.output)
-			.strip;
 		if (ver.empty) {
 			logWarn(`Could not probe the compiler version for "%s". ` ~
 				`Toolchain requirements might be ineffective`, build_platform.compiler);

diff --git a/source/dub/compilers/utils.d b/source/dub/compilers/utils.d
@@ -266,16 +266,28 @@ private enum probeEndMark = "__dub_probe_end__";
 
 	See_Also: `readPlatformProbe`
 */
-NativePath generatePlatformProbeFile()
+NativePath generatePlatformProbeFile(bool betterC = false)()
 {
 	import dub.internal.vibecompat.core.file;
 	import dub.internal.vibecompat.data.json;
 	import dub.internal.utils;
 	import std.string : format;
+	enum moduleInfo = betterC ? q{
+		module object;
+		alias string = const(char)[];
+		alias size_t = uint;
+		template _d_arrayappendcTXImpl(Tarr : T[], T){
+			ref Tarr _d_arrayappendcTX(return ref scope Tarr px, size_t n) @trusted pure nothrow{return px;}
+		}
+		const(char)[][] _d_arrayappendcTX(return scope ref const(char)[][] px, size_t n){return px;}
+		Tarr _d_arrayappendT(Tarr : T[], T)(return ref scope Tarr x, scope Tarr y){return x;}
+	} : q{
+		module dub_platform_probe;
+	};
 
 	// try to not use phobos in the probe to avoid long import times
 	enum probe = q{
-		module dub_platform_probe;
+		%1$s
 
 		template toString(int v) { enum toString = v.stringof; }
 		string stringArray(string[] ary) {
@@ -288,7 +300,7 @@ NativePath generatePlatformProbeFile()
 			return res;
 		}
 
-		pragma(msg, `%1$s`
+		pragma(msg, `%2$s`
 			~ '\n' ~ `{`
 			~ '\n' ~ `  "compiler": "`~ determineCompiler() ~ `",`
 			~ '\n' ~ `  "frontendVersion": ` ~ toString!__VERSION__ ~ `,`
@@ -300,13 +312,13 @@ NativePath generatePlatformProbeFile()
 			~ '\n' ~ `    ` ~ determineArchitecture().stringArray
 			~ '\n' ~ `   ],`
 			~ '\n' ~ `}`
-			~ '\n' ~ `%2$s`);
+			~ '\n' ~ `%3$s`);
 
-		string[] determinePlatform() { %3$s }
-		string[] determineArchitecture() { %4$s }
-		string determineCompiler() { %5$s }
+		string[] determinePlatform() { %4$s }
+		string[] determineArchitecture() { %5$s }
+		string determineCompiler() { %6$s }
 
-		}.format(probeBeginMark, probeEndMark, platformCheck, archCheck, compilerCheck);
+		}.format(moduleInfo, probeBeginMark, probeEndMark, platformCheck, archCheck, compilerCheck);
 
 	auto path = getTempFile("dub_platform_probe", ".d");
 	writeFile(path, probe);
@@ -321,14 +333,15 @@ NativePath generatePlatformProbeFile()
 */
 BuildPlatform readPlatformJsonProbe(string output)
 {
-	import std.algorithm : map;
+	import std.algorithm : map, max;
 	import std.array : array;
 	import std.exception : enforce;
+	import std.ascii : newline;
 	import std.string;
 
 	// work around possible additional output of the compiler
-	auto idx1 = output.indexOf(probeBeginMark);
-	auto idx2 = output.lastIndexOf(probeEndMark);
+	auto idx1 = output.indexOf(probeBeginMark~newline~"{");
+	auto idx2 = output[max(0,idx1) .. $].indexOf(probeEndMark) + idx1;
 	enforce(idx1 >= 0 && idx1 < idx2,
 		"Unexpected platform information output - does not contain a JSON object.");
 	output = output[idx1+probeBeginMark.length .. idx2];