[lld] 3ba3342 - [ELF] --warn-backrefs-exclude: use toString to match the documentation

[Fangrui Song via llvm-commits]

Author: Fangrui Song
Date: 2020-11-07T20:19:21-08:00
New Revision: 3ba3342232f425f6fcea2a063821194e6ff92789

URL: https://github.com/llvm/llvm-project/commit/3ba3342232f425f6fcea2a063821194e6ff92789
DIFF: https://github.com/llvm/llvm-project/commit/3ba3342232f425f6fcea2a063821194e6ff92789.diff

LOG: [ELF] --warn-backrefs-exclude: use toString to match the documentation

The pattern should patch `a.a(a.o)` instead of `a.a`

Added: 
    

Modified: 
    lld/ELF/Symbols.cpp
    lld/test/ELF/warn-backrefs.s

Removed: 
    


################################################################################
diff  --git a/lld/ELF/Symbols.cpp b/lld/ELF/Symbols.cpp
index eed0251c82e3..f38d9fab4500 100644
--- a/lld/ELF/Symbols.cpp
+++ b/lld/ELF/Symbols.cpp
@@ -377,9 +377,18 @@ bool elf::computeIsPreemptible(const Symbol &sym) {
 void elf::reportBackrefs() {
   for (auto &it : backwardReferences) {
     const Symbol &sym = *it.first;
-    warn("backward reference detected: " + sym.getName() + " in " +
-         toString(it.second.first) + " refers to " +
-         toString(it.second.second));
+    std::string to = toString(it.second.second);
+    // Some libraries have known problems and can cause noise. Filter them out
+    // with --warn-backrefs-exclude=. to may look like *.o or *.a(*.o).
+    bool exclude = false;
+    for (const llvm::GlobPattern &pat : config->warnBackrefsExclude)
+      if (pat.match(to)) {
+        exclude = true;
+        break;
+      }
+    if (!exclude)
+      warn("backward reference detected: " + sym.getName() + " in " +
+           toString(it.second.first) + " refers to " + to);
   }
 }
 
@@ -515,17 +524,6 @@ void Symbol::resolveUndefined(const Undefined &other) {
     // group assignment rule simulates the traditional linker's semantics.
     bool backref = config->warnBackrefs && other.file &&
                    file->groupId < other.file->groupId;
-    if (backref) {
-      // Some libraries have known problems and can cause noise. Filter them out
-      // with --warn-backrefs-exclude=.
-      StringRef name =
-          !file->archiveName.empty() ? file->archiveName : file->getName();
-      for (const llvm::GlobPattern &pat : config->warnBackrefsExclude)
-        if (pat.match(name)) {
-          backref = false;
-          break;
-        }
-    }
     fetch();
 
     // We don't report backward references to weak symbols as they can be

diff  --git a/lld/test/ELF/warn-backrefs.s b/lld/test/ELF/warn-backrefs.s
index a1b186fc98b1..6912955700f9 100644
--- a/lld/test/ELF/warn-backrefs.s
+++ b/lld/test/ELF/warn-backrefs.s
@@ -20,8 +20,8 @@
 # RUN: ld.lld --warn-backrefs %t2.a %t1.o -o /dev/null 2>&1 | FileCheck %s
 # RUN: ld.lld --warn-backrefs %t2.a '-(' %t1.o '-)' -o /dev/null 2>&1 | FileCheck %s
 # RUN: ld.lld --warn-backrefs --warn-backrefs-exclude='*3.a' %t2.a %t1.o -o /dev/null 2>&1 | FileCheck %s
-# RUN: ld.lld --fatal-warnings --warn-backrefs --warn-backrefs-exclude='*2.a' %t2.a %t1.o -o /dev/null
-# RUN: ld.lld --fatal-warnings --warn-backrefs --warn-backrefs-exclude '*2.a' \
+# RUN: ld.lld --fatal-warnings --warn-backrefs --warn-backrefs-exclude='*2.a(*2.o)' %t2.a %t1.o -o /dev/null
+# RUN: ld.lld --fatal-warnings --warn-backrefs --warn-backrefs-exclude '*2.a(*2.o)' \
 # RUN:   --warn-backrefs-exclude not_exist %t2.a %t1.o -o /dev/null
 ## Without --warn-backrefs, --warn-backrefs-exclude is ignored.
 # RUN: ld.lld --fatal-warnings --warn-backrefs-exclude=not_exist %t2.a %t1.o -o /dev/null
@@ -35,7 +35,7 @@
 # RUN: echo 'GROUP("%t2.a")' > %t3.lds
 # RUN: ld.lld --warn-backrefs %t3.lds %t1.o -o /dev/null 2>&1 | FileCheck %s
 # RUN: ld.lld --fatal-warnings --warn-backrefs '-(' %t3.lds %t1.o '-)' -o /dev/null
-# RUN: ld.lld --fatal-warnings --warn-backrefs --warn-backrefs-exclude='*2.a' -o /dev/null %t3.lds %t1.o
+# RUN: ld.lld --fatal-warnings --warn-backrefs --warn-backrefs-exclude='*2.a(*2.o)' -o /dev/null %t3.lds %t1.o
 ## If a lazy definition appears after the backward reference, don't warn.
 # RUN: ld.lld --fatal-warnings --warn-backrefs %t3.lds %t1.o %t3.lds -o /dev/null