link crt1.o when using libc

Author: MESYETI

source/app.d

@@ -37,6 +37,7 @@ Flags:
 	-dv VER    - Disables VER
 	-h FILE    - Puts the contents of FILE at the top of the assembly output
 	-bo OPT    - Backend option, see below
+	-ka        - Keep assembly
 
 Backends:
 	rm86    - Real mode x86 and MS-DOS
@@ -76,6 +77,7 @@ int main(string[] args) {
 	string[]        disabled;
 	string          header;
 	string[]        backendOpts;
+	bool            keepAssembly;
 
 	for (size_t i = 1; i < args.length; ++ i) {
 		if (args[i][0] == '-') {
@@ -238,6 +240,10 @@ int main(string[] args) {
 					backendOpts ~= args[i];
 					break;
 				}
+				case "-ka": {
+					keepAssembly = true;
+					break;
+				}
 				default: {
 					stderr.writefln("Unknown flag '%s'", args[i]);
 					return 1;
@@ -299,6 +305,7 @@ int main(string[] args) {
 	compiler.backend.useDebug       = doDebug;
 	compiler.backend.exportSymbols  = exportSymbols;
 	compiler.backend.link          ~= link;
+	backend.keepAssembly            = keepAssembly;
 
 	versions ~= compiler.backend.GetVersions();
 

source/backends/linux86.d

@@ -175,9 +175,30 @@ class BackendLinux86 : CompilerBackend {
 			linkCommand ~= " -dynamic-linker /lib64/ld-linux-x86-64.so.2";
 		}
 
+		if (useLibc) {
+			string[] possiblePaths = [
+				"/usr/lib/crt1.o",
+				"/usr/lib/x86_64-linux-gnu/crt1.o"
+			];
+			bool crt1;
+
+			foreach (ref path ; possiblePaths) {
+				if (exists(path)) {
+					crt1 = true;
+					linkCommand ~= format(" %s", path);
+				}
+			}
+			
+			linkCommand ~= " /usr/lib/crt1.o";
+		}
+
 		ret ~= linkCommand;
 
-		return ret ~ format("rm %s.asm %s.o", compiler.outFile, compiler.outFile);
+		if (!keepAssembly) {
+			 ret ~= format("rm %s.asm %s.o", compiler.outFile, compiler.outFile);
+		}
+		
+		return ret;
 	}
 
 	override long MaxInt() => -1;
@@ -201,7 +222,8 @@ class BackendLinux86 : CompilerBackend {
 	}
 
 	override void Init() {
-		if (!useLibc) output ~= "global _start\n";
+		if (useLibc) output ~= "global main\n";
+		else         output ~= "global _start\n";
 
 		output ~= "section .text\n";
 

source/backends/rm86.d

@@ -147,7 +147,7 @@ class BackendRM86 : CompilerBackend {
 	override string[] FinalCommands() => [
 		format("mv %s %s.asm", compiler.outFile, compiler.outFile),
 		format("nasm -f bin %s.asm -o %s", compiler.outFile, compiler.outFile),
-		format("rm %s.asm", compiler.outFile)
+		keepAssembly? "" : format("rm %s.asm", compiler.outFile)
 	];
 
 	override long MaxInt() => 0xFFFF;

source/backends/uxn.d

@@ -109,7 +109,7 @@ class BackendUXN : CompilerBackend {
 	override string[] FinalCommands() => [
 		format("mv %s %s.tal", compiler.outFile, compiler.outFile),
 		format("uxnasm %s.tal %s", compiler.outFile, compiler.outFile),
-		format("rm %s.tal", compiler.outFile)
+		keepAssembly? "" : format("rm %s.tal", compiler.outFile)
 	];
 
 	override long MaxInt() => 0xFFFF;

source/compiler.d

@@ -18,6 +18,7 @@ class CompilerBackend {
 	bool     useDebug;
 	bool     exportSymbols;
 	string[] link;
+	bool     keepAssembly;
 
 	abstract string[] GetVersions();
 	abstract string[] FinalCommands();