[ELF] - Do not report multiple errors for single one in ScriptLexer::setError.

[grimar]

Summary

Previously up to 3 errors were reported at once,
with patch we always will report only one,
just like in other linker code.

[ruiu]

LGTM. Thank you for doing this!

lld/trunk/ELF/ScriptLexer.cpp

 
 ScriptLexer::ScriptLexer(MemoryBufferRef MB) { tokenize(MB); }
 
 // We don't want to record cascading errors. Keep only the first one.
 void ScriptLexer::setError(const Twine &Msg) {
   if (ErrorCount)
     return;
 
-  if (!Pos) {
-    error(getCurrentLocation() + ": " + Msg);
-    return;
-  }
-
-  std::string S = getCurrentLocation() + ": ";
-  error(S + Msg);
-  error(S + getLine());
-  error(S + std::string(getColumnNumber(), ' ') + "^");
+  std::string S = (getCurrentLocation() + ": " + Msg).str();
+  if (Pos)
+    S += "\n>>> " + getLine().str() + "\n>>> " +
+         std::string(getColumnNumber(), ' ') + "^";
+  error(S);
 }
 
 // Split S into linker script tokens.
 void ScriptLexer::tokenize(MemoryBufferRef MB) {
   std::vector<StringRef> Vec;
   MBs.push_back(MB);
   StringRef S = MB.getBuffer();
   StringRef Begin = S;

lld/trunk/test/ELF/linkerscript/diagnostic.s

 
 ## Check that text of lines and pointer to 'bad' token are working ok.
 # RUN: echo "UNKNOWN_TAG {" > %t.script
 # RUN: echo ".text : { *(.text) }" >> %t.script
 # RUN: echo ".keep : { *(.keep) }" >> %t.script
 # RUN: echo ".temp : { *(.temp) } }" >> %t.script
 # RUN: not ld.lld -shared %t -o %t1 --script %t.script 2>&1 | \
 # RUN:   FileCheck -check-prefix=ERR6 -strict-whitespace %s
-# ERR6:      error: {{.*}}.script:1:
-# ERR6-NEXT: error: {{.*}}.script:1: UNKNOWN_TAG {
-# ERR6-NEXT: error: {{.*}}.script:1: ^
+# ERR6:      error: {{.*}}.script:1: unknown directive: UNKNOWN_TAG
+# ERR6-NEXT: >>> UNKNOWN_TAG {
+# ERR6-NEXT: >>> ^
 
 ## One more check that text of lines and pointer to 'bad' token are working ok.
 # RUN: echo "SECTIONS {" > %t.script
 # RUN: echo ".text : { *(.text) }" >> %t.script
 # RUN: echo ".keep : { *(.keep) }" >> %t.script
 # RUN: echo "boom .temp : { *(.temp) } }" >> %t.script
 # RUN: not ld.lld -shared %t -o %t1 --script %t.script 2>&1 | \
 # RUN:   FileCheck -check-prefix=ERR7 -strict-whitespace %s
 # ERR7:      error: {{.*}}.script:4: malformed number: .temp
-# ERR7-NEXT: error: {{.*}}.script:4: boom .temp : { *(.temp) } }
-# ERR7-NEXT: error: {{.*}}.script:4:      ^
+# ERR7-NEXT: >>> boom .temp : { *(.temp) } }
+# ERR7-NEXT: >>>      ^
 
 ## Check tokenize() error
 # RUN: echo "SECTIONS {}" > %t.script
 # RUN: echo "\"" >> %t.script
 # RUN: not ld.lld -shared %t -o %t1 --script %t.script 2>&1 | \
 # RUN:   FileCheck -check-prefix=ERR8 -strict-whitespace %s
 # ERR8: {{.*}}.script:2: unclosed quote
 

 # RUN: echo "SECTIONS {" > %t.script.inc
 # RUN: echo ".text : { *(.text) }" >> %t.script.inc
 # RUN: echo ".keep : { *(.keep) }" >> %t.script.inc
 # RUN: echo "boom .temp : { *(.temp) } }" >> %t.script.inc
 # RUN: echo "INCLUDE \"%t.script.inc\"" > %t.script
 # RUN: not ld.lld -shared %t -o %t1 --script %t.script 2>&1 | \
 # RUN:   FileCheck -check-prefix=ERR10 -strict-whitespace %s
 # ERR10:      error: {{.*}}.script.inc:4: malformed number: .temp
-# ERR10-NEXT: error: {{.*}}.script.inc:4: boom .temp : { *(.temp) } }
-# ERR10-NEXT: error: {{.*}}.script.inc:4:      ^
+# ERR10-NEXT: >>> boom .temp : { *(.temp) } }
+# ERR10-NEXT: >>>      ^
 
 ## Check error reporting in script with INCLUDE directive.
 # RUN: echo "SECTIONS {" > %t.script.inc
 # RUN: echo ".text : { *(.text) }" >> %t.script.inc
 # RUN: echo ".keep : { *(.keep) }" >> %t.script.inc
 # RUN: echo ".temp : { *(.temp) } }" >> %t.script.inc
 # RUN: echo "/* One line before INCLUDE */" > %t.script
 # RUN: echo "INCLUDE \"%t.script.inc\"" >> %t.script
 # RUN: echo "/* One line ater INCLUDE */" >> %t.script
 # RUN: echo "Error" >> %t.script
 # RUN: not ld.lld -shared %t -o %t1 --script %t.script 2>&1 | \
 # RUN:   FileCheck -check-prefix=ERR11 -strict-whitespace %s
 # ERR11: error: {{.*}}.script:4: unexpected EOF

lld/trunk/test/ELF/linkerscript/linkerscript.s

 # RUN: ld.lld %t.script1
 # RUN: llvm-readobj %t2 > /dev/null
 
 # RUN: echo "INCLUDE \"foo.script\"" > %t.script
 # RUN: echo "OUTPUT(\"%t.out\")" > %T/foo.script
 # RUN: not ld.lld %t.script > %t.log 2>&1
 # RUN: FileCheck -check-prefix=INCLUDE_ERR %s < %t.log
 # INCLUDE_ERR: error: {{.+}}.script:1: cannot open foo.script
-# INCLUDE_ERR-NEXT: error: {{.+}}.script:1: INCLUDE "foo.script"
+# INCLUDE_ERR-NEXT: INCLUDE "foo.script"
 # RUN: ld.lld -L %T %t.script %t
 
 # RUN: echo "FOO(BAR)" > %t.script
 # RUN: not ld.lld -o foo %t.script > %t.log 2>&1
 # RUN: FileCheck -check-prefix=ERR1 %s < %t.log
 
 # ERR1: unknown directive: FOO
 
 .globl _start, _label
 _start:
   ret
 _label:
   ret