[lld-macho] Make ObjC category checker print the source file name of …

…category (llvm#80221)

When printing category conflicts in the ObjC category checker, also
print the source file name of the problematic categories. Currently we
only print the object file name. This change is mostly useful only for
thinLTO builds, where the object file name will be of form
999.arm64.lto.o and thus does not reveal any information about the
original source file.

---------

Co-authored-by: Alex Borcan <alexborcan@meta.com>

lld/MachO/ObjC.cpp

@@ -237,12 +237,23 @@ void ObjcCategoryChecker::parseMethods(const ConcatInputSection *methodsIsec,
     StringRef newCatName =
         getReferentString(*containerIsec->getRelocAt(catLayout.nameOffset));
 
+    auto formatObjAndSrcFileName = [](const InputSection *section) {
+      lld::macho::InputFile *inputFile = section->getFile();
+      std::string result = toString(inputFile);
+
+      auto objFile = dyn_cast_or_null<ObjFile>(inputFile);
+      if (objFile && objFile->compileUnit)
+        result += " (" + objFile->sourceFile() + ")";
+
+      return result;
+    };
+
     StringRef containerType = mc.kind == MCK_Category ? "category" : "class";
     warn("method '" + methPrefix + methodName.val() +
          "' has conflicting definitions:\n>>> defined in category " +
-         newCatName + " from " + toString(containerIsec->getFile()) +
+         newCatName + " from " + formatObjAndSrcFileName(containerIsec) +
          "\n>>> defined in " + containerType + " " + containerName + " from " +
-         toString(mc.isec->getFile()));
+         formatObjAndSrcFileName(mc.isec));
   }
 }
 

lld/test/MachO/objc-category-conflicts.s

@@ -3,6 +3,9 @@
 # RUN: llvm-mc -filetype=obj -triple=x86_64-apple-macos11.0 -I %t %t/cat1.s -o %t/cat1.o
 # RUN: llvm-mc -filetype=obj -triple=x86_64-apple-macos11.0 -I %t %t/cat2.s -o %t/cat2.o
 # RUN: llvm-mc -filetype=obj -triple=x86_64-apple-macos11.0 -I %t %t/klass.s -o %t/klass.o
+# RUN: llvm-mc -filetype=obj -triple=x86_64-apple-macos11.0 -I %t %t/cat1.s -g -o %t/cat1_w_sym.o
+# RUN: llvm-mc -filetype=obj -triple=x86_64-apple-macos11.0 -I %t %t/cat2.s -g -o %t/cat2_w_sym.o
+# RUN: llvm-mc -filetype=obj -triple=x86_64-apple-macos11.0 -I %t %t/klass.s -g -o %t/klass_w_sym.o
 # RUN: llvm-mc -filetype=obj -triple=x86_64-apple-macos11.0 -I %t %t/cat1.s --defsym MAKE_LOAD_METHOD=1 -o %t/cat1-with-load.o
 # RUN: llvm-mc -filetype=obj -triple=x86_64-apple-macos11.0 -I %t %t/cat2.s --defsym MAKE_LOAD_METHOD=1 -o %t/cat2-with-load.o
 # RUN: llvm-mc -filetype=obj -triple=x86_64-apple-macos11.0 -I %t %t/klass.s --defsym MAKE_LOAD_METHOD=1 -o %t/klass-with-load.o
@@ -14,6 +17,11 @@
 # RUN: %no-fatal-warnings-lld --check-category-conflicts -dylib -lobjc %t/libklass.dylib %t/cat1.o \
 # RUN:   %t/cat2.o -o /dev/null 2>&1 | FileCheck %s --check-prefix=CATCAT
 
+# RUN: %no-fatal-warnings-lld --check-category-conflicts -dylib -lobjc %t/klass_w_sym.o %t/cat1_w_sym.o %t/cat2_w_sym.o -o \
+# RUN:   /dev/null 2>&1 | FileCheck %s --check-prefixes=CATCLS_W_SYM,CATCAT_W_SYM
+# RUN: %no-fatal-warnings-lld --check-category-conflicts -dylib -lobjc %t/libklass.dylib %t/cat1_w_sym.o \
+# RUN:   %t/cat2_w_sym.o -o /dev/null 2>&1 | FileCheck %s --check-prefix=CATCAT_W_SYM
+
 ## Check that we don't emit spurious warnings around the +load method while
 ## still emitting the other warnings. Note that we have made separate
 ## `*-with-load.s` files for ease of comparison with ld64; ld64 will not warn
@@ -45,6 +53,24 @@
 # CATCAT-NEXT: >>> defined in category Cat2 from {{.*}}cat2{{.*}}.o
 # CATCAT-NEXT: >>> defined in category Cat1 from {{.*}}cat1{{.*}}.o
 
+
+# CATCLS_W_SYM:      warning: method '+s1' has conflicting definitions:
+# CATCLS_W_SYM-NEXT: >>> defined in category Cat1 from {{.*}}cat1_w_sym{{.*}}.o ({{.*}}cat1.s{{.*}})
+# CATCLS_W_SYM-NEXT: >>> defined in class Foo from {{.*}}klass_w_sym{{.*}}.o ({{.*}}klass.s{{.*}})
+
+# CATCLS_W_SYM:      warning: method '-m1' has conflicting definitions:
+# CATCLS_W_SYM-NEXT: >>> defined in category Cat1 from {{.*}}cat1_w_sym{{.*}}.o ({{.*}}cat1.s{{.*}})
+# CATCLS_W_SYM-NEXT: >>> defined in class Foo from {{.*}}klass_w_sym{{.*}}.o ({{.*}}klass.s{{.*}})
+
+# CATCAT_W_SYM:      warning: method '+s2' has conflicting definitions:
+# CATCAT_W_SYM-NEXT: >>> defined in category Cat2 from {{.*}}cat2_w_sym{{.*}}.o ({{.*}}cat2.s{{.*}})
+# CATCAT_W_SYM-NEXT: >>> defined in category Cat1 from {{.*}}cat1_w_sym{{.*}}.o ({{.*}}cat1.s{{.*}})
+
+# CATCAT_W_SYM:      warning: method '-m2' has conflicting definitions:
+# CATCAT_W_SYM-NEXT: >>> defined in category Cat2 from {{.*}}cat2_w_sym{{.*}}.o ({{.*}}cat2.s{{.*}})
+# CATCAT_W_SYM-NEXT: >>> defined in category Cat1 from {{.*}}cat1_w_sym{{.*}}.o ({{.*}}cat1.s{{.*}})
+
+
 #--- cat1.s
 
 .include "objc-macros.s"
@@ -55,7 +81,7 @@
 ## +(void) s1;
 ## +(void) s2;
 ## @end
-## 
+##
 ## @implementation Foo(Cat1)
 ## -(void) m1 {}
 ## -(void) m2 {}
@@ -114,7 +140,7 @@ __OBJC_$_CATEGORY_CLASS_METHODS_Foo_$_Cat1:
 ## -(void) m2;
 ## +(void) s2;
 ## @end
-## 
+##
 ## @implementation Foo(Cat2)
 ## -(void) m2 {}
 ## +(void) s2 {}