[Xamarin.Android.Build.Tasks] Fix -int.ToString() for locales (#7941)

Fixes: #7939

Context: dotnet/runtime#13363
Context: https://www.unicode.org/charts/PDF/U2200.pdf (page 2)
Context: 5271f3e

The LLVM IR generator (5271f3e) outputs a number of integer values,
relying on the standard `int.ToString()` method to convert the value
to a string.  However, since .NET 6, this conversion is culture-
sensitive and in certain cultures (list below) it will output the
minus sign not as the "standard" ASCII \u002d character `-` but
instead as something else (see complete list below for details).

This breaks LLVM LLC:

	llc: environment.arm64-v8a.ll:554:7: error: expected value token
	  stderr |                 i32 −1, ; apk_fd

Fix the problem by using invariant culture when converting ***all***
integers and unknown objects to strings.  The reason all of them are
converted in this way is to avoid future changes to ICU and/or .NET
to-string conversion that might affect the resulting integer format.

Workaround: export `$LANG` to a locale that uses 0x2D `-` for
negation, e.g. `LANG=C`.

Locales/cultures affected by this issue are as follows:

  * ARABIC LETTER MARK + HYPHEN-MINUS `؜-` (\u061c \u002d): 26 cultures
    * ar
    * ar-001
    * ar-BH
    * ar-DJ
    * ar-EG
    * ar-ER
    * ar-IL
    * ar-IQ
    * ar-JO
    * ar-KM
    * ar-KW
    * ar-LB
    * ar-MR
    * ar-OM
    * ar-PS
    * ar-QA
    * ar-SA
    * ar-SD
    * ar-SO
    * ar-SS
    * ar-SY
    * ar-TD
    * ar-YE
    * sd
    * sd-Arab
    * sd-Arab-PK
  * LEFT-TO-RIGHT MARK + HYPHEN-MINUS `‎-` (\u200e \u002d): 10 cultures
    * ar-AE
    * ar-DZ
    * ar-EH
    * ar-LY
    * ar-MA
    * ar-TN
    * he
    * he-IL
    * ur
    * ur-PK
  * RIGHT-TO-LEFT MARK + HYPHEN-MINUS `‏-` (\u200f \u002d): 3 cultures
    * ckb
    * ckb-IQ
    * ckb-IR
  * MINUS SIGN `−` (\u2212): 38 cultures
    * et
    * et-EE
    * eu
    * eu-ES
    * fi
    * fi-FI
    * fo
    * fo-DK
    * fo-FO
    * gsw
    * gsw-CH
    * gsw-FR
    * gsw-LI
    * hr
    * hr-BA
    * hr-HR
    * ksh
    * ksh-DE
    * lt
    * lt-LT
    * nb
    * nb-NO
    * nb-SJ
    * nn
    * nn-NO
    * no
    * rm
    * rm-CH
    * se
    * se-FI
    * se-NO
    * se-SE
    * sl
    * sl-SI
    * sv
    * sv-AX
    * sv-FI
    * sv-SE
  * LEFT-TO-RIGHT MARK + MINUS SIGN `‎−` (\u200e \u2212): 3 cultures
    * fa
    * fa-AF
    * fa-IR
  * LEFT-TO-RIGHT MARK + HYPHEN-MINUS + LEFT-TO-RIGHT MARK `‎-‎` (\u200e \u002d \u002e): 16 cultures
    * ks
    * ks-Arab
    * ks-Arab-IN
    * lrc
    * lrc-IQ
    * lrc-IR
    * mzn
    * mzn-IR
    * pa-Arab
    * pa-Arab-PK
    * ps
    * ps-AF
    * ps-PK
    * ur-IN
    * uz-Arab
    * uz-Arab-AF

Update `BuildTest2.BuildBasicApplication()` to export
`LANG=sv_SE.UTF-8` as part of the `dotnet build` command to test this
scenario on macOS and Linux.  (This change is ignored on Windows.)

src/Xamarin.Android.Build.Tasks/Tests/Xamarin.Android.Build.Tests/BuildTest2.cs

@@ -105,14 +105,22 @@ public static string [] SupportedTargetFrameworks ()
 		}
 
 		[Test]
-		public void BuildBasicApplication ([ValueSource (nameof (SupportedTargetFrameworks))] string tfv, [Values (true, false)] bool isRelease)
+		public void BuildBasicApplication ([ValueSource (nameof (SupportedTargetFrameworks))] string tfv, [Values (true, false)] bool isRelease, [Values ("", "en_US.UTF-8", "sv_SE.UTF-8")] string langEnvironmentVariable)
 		{
 			var proj = new XamarinAndroidApplicationProject {
 				IsRelease = isRelease,
 				TargetFrameworkVersion = tfv,
 			};
+
+			Dictionary<string, string> envvar = null;
+			if (!String.IsNullOrEmpty (langEnvironmentVariable)) {
+				envvar = new Dictionary<string, string> (StringComparer.OrdinalIgnoreCase) {
+					{"LANG", langEnvironmentVariable},
+				};
+			}
+
 			using (var b = CreateApkBuilder ()) {
-				Assert.IsTrue (b.Build (proj), "Build should have succeeded.");
+				Assert.IsTrue (b.Build (proj, environmentVariables: envvar), "Build should have succeeded.");
 			}
 		}
 

src/Xamarin.Android.Build.Tasks/Utilities/ApplicationConfigNativeAssemblyGenerator.cs

@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using System.Globalization;
 using System.IO;
 
 using Java.Interop.Tools.TypeNameMappings;
@@ -253,7 +254,7 @@ List<StructureInstance<DSOCacheEntry>> InitDSOCache ()
 					continue;
 				}
 
-				dsos.Add ((name, $"dsoName{dsos.Count}", ELFHelper.IsEmptyAOTLibrary (log, item.ItemSpec)));
+				dsos.Add ((name, $"dsoName{dsos.Count.ToString (CultureInfo.InvariantCulture)}", ELFHelper.IsEmptyAOTLibrary (log, item.ItemSpec)));
 			}
 
 			var dsoCache = new List<StructureInstance<DSOCacheEntry>> ();

src/Xamarin.Android.Build.Tasks/Utilities/LlvmIrGenerator/FunctionAttributes.cs

@@ -1,5 +1,6 @@
 using System;
 using System.Text;
+using System.Globalization;
 
 namespace Xamarin.Android.Tasks.LLVMIR
 {
@@ -113,7 +114,7 @@ public AlignstackFunctionAttribute (uint powerOfTwoAlignment)
 
 		protected override void RenderParams (StringBuilder sb)
 		{
-			sb.Append (alignment);
+			sb.Append (alignment.ToString (CultureInfo.InvariantCulture));
 		}
 	}
 
@@ -165,13 +166,13 @@ public AllocsizeFunctionAttribute (uint elementSize, uint? numberOfElements = nu
 
 		protected override void RenderParams (StringBuilder sb)
 		{
-			sb.Append (elementSize);
+			sb.Append (elementSize.ToString (CultureInfo.InvariantCulture));
 			if (!numberOfElements.HasValue) {
 				return;
 			}
 
 			sb.Append (", ");
-			sb.Append (numberOfElements.Value);
+			sb.Append (numberOfElements.Value.ToString (CultureInfo.InvariantCulture));
 		}
 	}
 
@@ -701,13 +702,13 @@ public VscaleRangeFunctionAttribute (uint min, uint? max = null)
 
 		protected override void RenderParams (StringBuilder sb)
 		{
-			sb.Append (min);
+			sb.Append (min.ToString (CultureInfo.InvariantCulture));
 			if (!max.HasValue) {
 				return;
 			}
 
 			sb.Append (", ");
-			sb.Append (max.Value);
+			sb.Append (max.Value.ToString (CultureInfo.InvariantCulture));
 		}
 	}
 
@@ -721,7 +722,7 @@ public MinLegalVectorWidthFunctionAttribute (uint size)
 			this.size = size;
 		}
 
-		protected override void RenderAssignedValue (StringBuilder sb) => sb.Append (size);
+		protected override void RenderAssignedValue (StringBuilder sb) => sb.Append (size.ToString (CultureInfo.InvariantCulture));
 	}
 
 	class StackProtectorBufferSizeFunctionAttribute : LLVMFunctionAttribute
@@ -734,7 +735,7 @@ public StackProtectorBufferSizeFunctionAttribute (uint size)
 			this.size = size;
 		}
 
-		protected override void RenderAssignedValue (StringBuilder sb) => sb.Append (size);
+		protected override void RenderAssignedValue (StringBuilder sb) => sb.Append (size.ToString (CultureInfo.InvariantCulture));
 	}
 
 	class TargetCpuFunctionAttribute : LLVMFunctionAttribute

src/Xamarin.Android.Build.Tasks/Utilities/LlvmIrGenerator/LlvmIrFunction.cs

@@ -3,7 +3,6 @@
 using System.Globalization;
 using System.Linq;
 using System.Text;
-using System.Reflection;
 
 namespace Xamarin.Android.Tasks.LLVMIR
 {

src/Xamarin.Android.Build.Tasks/Utilities/LlvmIrGenerator/LlvmIrGenerator.Code.cs

@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using System.Globalization;
 using System.IO;
 using System.Text;
 
@@ -52,7 +53,7 @@ public void WriteFunctionStart (LlvmIrFunction function, string? comment = null)
 			WriteFunctionParameters (function.Parameters, writeNames: true);
 			Output.Write(") local_unnamed_addr ");
 			if (attributes != null) {
-				Output.Write ($"#{function.AttributeSetID}");
+				Output.Write ($"#{function.AttributeSetID.ToString (CultureInfo.InvariantCulture)}");
 			}
 			Output.WriteLine ();
 			Output.WriteLine ("{");
@@ -184,7 +185,7 @@ public void EmitStoreInstruction (LlvmIrFunction function, LlvmIrFunctionLocalVa
 			CodeRenderType (source);
 			Output.Write ($" %{source.Name}, ");
 			CodeRenderType (destination);
-			Output.WriteLine ($"* {destination.Reference}, align {GetTypeSize (destination.Type)}");
+			Output.WriteLine ($"* {destination.Reference}, align {GetTypeSize (destination.Type).ToString (CultureInfo.InvariantCulture)}");
 		}
 
 		/// <summary>
@@ -201,7 +202,7 @@ public LlvmIrFunctionLocalVariable EmitLoadInstruction (LlvmIrFunction function,
 
 			string variableType = sb.ToString ();
 			LlvmIrFunctionLocalVariable result = function.MakeLocalVariable (source, resultVariableName);
-			Output.WriteLine ($"{function.Indent}%{result.Name} = load {variableType}, {variableType}* @{source.Name}, align {PointerSize}");
+			Output.WriteLine ($"{function.Indent}%{result.Name} = load {variableType}, {variableType}* @{source.Name}, align {PointerSize.ToString (CultureInfo.InvariantCulture)}");
 
 			return result;
 		}
@@ -378,7 +379,8 @@ public void EmitLabel (LlvmIrFunction function, string labelName)
 							Output.Write ("nonnull ");
 						}
 
-						Output.Write ($"align {PointerSize} dereferenceable({PointerSize}) ");
+						string ptrSize = PointerSize.ToString (CultureInfo.InvariantCulture);
+						Output.Write ($"align {ptrSize} dereferenceable({ptrSize}) ");
 
 						if (argument.Value is LlvmIrVariableReference variableRef) {
 							bool needBitcast = parameter.Type != argument.Type;
@@ -409,7 +411,7 @@ public void EmitLabel (LlvmIrFunction function, string labelName)
 				if (!FunctionAttributes.ContainsKey (AttributeSetID)) {
 					throw new InvalidOperationException ($"Unknown attribute set ID {AttributeSetID}");
 				}
-				Output.Write ($" #{AttributeSetID}");
+				Output.Write ($" #{AttributeSetID.ToString (CultureInfo.InvariantCulture)}");
 			}
 			Output.WriteLine ();
 
@@ -538,7 +540,7 @@ void WriteAttributeSets ()
 
 			void WriteSet (int id, TextWriter output)
 			{
-				output.Write ($"attributes #{id} = {{ ");
+				output.Write ($"attributes #{id.ToString (CultureInfo.InvariantCulture)} = {{ ");
 				foreach (LLVMFunctionAttribute attr in FunctionAttributes[id]) {
 					output.Write (attr.Render ());
 					output.Write (' ');