Make last conflicting option take precedence

lib/LinkerWrapper/GnuLdDriver.cpp

@@ -328,12 +328,9 @@ bool GnuLdDriver::processOptions(llvm::opt::InputArgList &Args) {
   if (llvm::opt::Arg *arg = Args.getLastArg(T::sysroot))
     Config.setSysRoot(arg->getValue());
 
-  // --fatal-warnings
-  Config.options().setFatalWarnings(Args.hasArg(T::fatal_warnings));
-
-  // --no-fatal-warnings
-  if (Args.hasArg(T::no_fatal_warnings))
-    Config.options().setFatalWarnings(false);
+  // --[no-]fatal-warnings
+  Config.options().setFatalWarnings(
+      Args.hasFlag(T::fatal_warnings, T::no_fatal_warnings, /*default=*/false));
 
   // --opt-record-file
   if (Args.hasArg(T::opt_record_file)) {
@@ -469,8 +466,9 @@ bool GnuLdDriver::processOptions(llvm::opt::InputArgList &Args) {
     }
   }
 
-  // --export-dynamic, -E
-  Config.options().setExportDynamic(Args.hasArg(T::export_dynamic));
+  // --[no-]export-dynamic, -E
+  Config.options().setExportDynamic(
+      Args.hasFlag(T::export_dynamic, T::no_export_dynamic, /*default=*/false));
 
   // --export-dynamic-symbol
   for (auto *Arg : Args.filtered(T::export_dynamic_symbol))
@@ -572,18 +570,14 @@ bool GnuLdDriver::processOptions(llvm::opt::InputArgList &Args) {
     }
   }
 
-  // --warn-shared-textrel
-  if (Args.hasArg(T::warn_shared_textrel))
-    Config.options().setWarnSharedTextrel(true);
+  // --[no-]warn-shared-textrel
+  Config.options().setWarnSharedTextrel(Args.hasFlag(
+      T::warn_shared_textrel, T::no_warn_shared_textrel, /*default=*/false));
 
   // --warn-common
   if (Args.hasArg(T::warn_common))
     Config.options().setWarnCommon();
 
-  // --no-warn-shared_textrel
-  if (Args.hasArg(T::no_warn_shared_textrel))
-    Config.options().setWarnSharedTextrel(false);
-
   // --enable-newdtags, --disable-newdtags
   if (Args.hasArg(T::enable_newdtags) && Args.hasArg(T::disable_newdtags)) {
     errs() << "Cannot specify enable and disable  DTAGS at same time!\n";
@@ -619,34 +613,31 @@ bool GnuLdDriver::processOptions(llvm::opt::InputArgList &Args) {
       T::record_command_line, T::no_record_command_line, /*default=*/false);
   Config.options().setRecordCommandLine(recordCommandLine);
 
-  // --emit-relocs
-  if (Args.hasArg(T::emit_relocs)) {
-    Config.options().setEmitGNUCompatRelocs(true);
-    Config.options().setEmitRelocs(true);
+  // --[no-]emit-relocs
+  bool emitRelocs =
+      Args.hasFlag(T::emit_relocs, T::no_emit_relocs, /*default=*/false);
+  Config.options().setEmitGNUCompatRelocs(emitRelocs);
+  Config.options().setEmitRelocs(emitRelocs);
+  if (emitRelocs)
     Config.addCommandLine(Table->getOptionName(T::emit_relocs), true);
-  }
 
   // --emit-relocs-llvm
   if (Args.hasArg(T::emit_relocs_llvm))
     Config.options().setEmitRelocs(true);
 
-  // --no-emit-relocs
-  if (Args.hasArg(T::no_emit_relocs)) {
-    Config.options().setEmitGNUCompatRelocs(false);
-    Config.options().setEmitRelocs(false);
-  }
-
   // --no-merge-strings
   Config.options().setMergeStrings(!Args.hasArg(T::no_merge_strings));
   Config.addCommandLine(Table->getOptionName(T::no_merge_strings),
                         Args.hasArg(T::no_merge_strings));
 
-  // --{no-}warn-mismatch
-  if (Args.getLastArg(T::no_warn_mismatch))
-    Config.options().setWarnMismatch(false);
-
-  if (Args.getLastArg(T::warn_mismatch))
-    Config.options().setWarnMismatch(true);
+  // --[no-]warn-mismatch
+  // This flag defaults to none so only set it if at least one of the two flags
+  // are present.
+  if (Args.getLastArg(T::warn_mismatch) ||
+      Args.getLastArg(T::no_warn_mismatch)) {
+    Config.options().setWarnMismatch(
+        Args.hasFlag(T::warn_mismatch, T::no_warn_mismatch, /*default=*/true));
+  }
 
   // --no-trampolines
   if (Args.hasArg(T::no_trampolines)) {
@@ -687,9 +678,15 @@ bool GnuLdDriver::processOptions(llvm::opt::InputArgList &Args) {
   }
   Config.addCommandLine(Table->getOptionName(T::flto_options), ltoOptions);
 
-  // --no-align-segments
-  if (Args.hasArg(T::no_align_segments))
-    Config.options().setAlignSegments(false);
+  // --[no-]align-segments
+  // This flag sets the same thing as --script, -T, --[no-]omagic, -N so only
+  // set it if at least one of the two flags are present.
+  if (Args.getLastArg(T::align_segments) ||
+      Args.getLastArg(T::no_align_segments)) {
+    bool alignSegments =
+        Args.hasFlag(T::align_segments, T::no_align_segments, /*default=*/true);
+    Config.options().setAlignSegments(alignSegments);
+  }
 
   bool enableFatalInternalErrors = Args.hasFlag(
       T::fatal_internal_errors, T::no_fatal_internal_errors, /*default=*/false);
@@ -1000,8 +997,9 @@ bool GnuLdDriver::processOptions(llvm::opt::InputArgList &Args) {
 
   // Disable --gc-sections, --print-gc-sections for Partial Linking.
   if (Config.codeGenType() != eld::LinkerConfig::Object) {
-    // --gc-sections
-    bool enableGC = Args.hasArg(T::gc_sections);
+    // --[no-]gc-sections
+    bool enableGC =
+        Args.hasFlag(T::gc_sections, T::no_gc_sections, /*default=*/false);
     Config.options().setGCSections(enableGC);
     Config.addCommandLine(Table->getOptionName(T::gc_sections), enableGC);
     // --print-gc-sections
@@ -1028,12 +1026,11 @@ bool GnuLdDriver::processOptions(llvm::opt::InputArgList &Args) {
   // Thread Options.
   //
 
-  // --no-threads, --threads
-  if (!Args.getLastArg(T::no_threads) || Args.getLastArg(T::threads)) {
+  // --[no-]threads
+  if (Args.hasFlag(T::threads, T::no_threads, /*default=*/true)) {
     Config.options().enableThreads();
     Config.addCommandLine(Table->getOptionName(T::threads), true);
-  } else if (Args.getLastArg(T::no_threads)) {
-    // --no-threads
+  } else {
     Config.options().disableThreads();
     Config.options().setNumThreads(1);
     Config.addCommandLine(Table->getOptionName(T::threads), false);
@@ -1112,13 +1109,15 @@ bool GnuLdDriver::processOptions(llvm::opt::InputArgList &Args) {
     }
   }
 
-  // --no-demangle
-  if (Args.getLastArg(T::no_demangle))
-    Config.options().setDemangleStyle("none");
-
-  // --demangle
-  if (Args.getLastArg(T::demangle))
-    Config.options().setDemangleStyle("demangle");
+  // --[no-]demangle
+  // This flag sets the same thing as --demangle-style so only set it if at
+  // least one of the two flags are present.
+  if (Args.getLastArg(T::demangle) || Args.getLastArg(T::no_demangle)) {
+    if (Args.hasFlag(T::demangle, T::no_demangle, /*default=*/true))
+      Config.options().setDemangleStyle("demangle");
+    else
+      Config.options().setDemangleStyle("none");
+  }
 
   /// --progress-bar
   if (Args.getLastArg(T::progress_bar))
@@ -1231,12 +1230,11 @@ bool GnuLdDriver::processOptions(llvm::opt::InputArgList &Args) {
   if (Args.hasArg(T::use_old_style_trampoline_name))
     Config.setUseOldStyleTrampolineName(true);
 
-  // --check-sections
-  if (Args.hasArg(T::enable_overlap_checks))
+  // --[no-]check-sections
+  if (Args.hasFlag(T::enable_overlap_checks, T::disable_overlap_checks,
+                   /*default=*/true))
     Config.options().setEnableCheckSectionOverlaps();
-
-  // --no-check-sections
-  if (Args.hasArg(T::disable_overlap_checks))
+  else
     Config.options().setDisableCheckSectionOverlaps();
 
   if (Args.hasArg(T::thin_archive_rule_matching_compatibility))
@@ -1279,13 +1277,11 @@ bool GnuLdDriver::processOptions(llvm::opt::InputArgList &Args) {
   if (Args.hasArg(T::noDefaultPlugins))
     Config.options().setNoDefaultPlugins();
 
-  // --no-omagic, --omagic, -N support
-  if (Args.hasArg(T::no_omagic))
-    Config.options().setOMagic(false);
-  else if (Args.hasArg(T::omagic)) {
+  // --[no-]omagic, -N
+  bool omagic = Args.hasFlag(T::omagic, T::no_omagic, /*default=*/false);
+  Config.options().setOMagic(omagic);
+  if (omagic)
     Config.options().setAlignSegments(false);
-    Config.options().setOMagic(true);
-  }
 
   // --plugin-activity-file=<file>
   if (llvm::opt::Arg *A = Args.getLastArg(T::PluginActivityFile)) {

lib/LinkerWrapper/RISCVLinkDriver.cpp

@@ -114,9 +114,10 @@ RISCVLinkDriver::parseOptions(ArrayRef<const char *> Args,
     return LINK_SUCCESS;
   }
 
-  // --no-relax
-  if (ArgList.hasArg(OPT_RISCVLinkOptTable::no_riscv_relax))
-    Config.options().setRISCVRelax(false);
+  // --[no-]relax
+  Config.options().setRISCVRelax(
+      ArgList.hasFlag(OPT_RISCVLinkOptTable::riscv_relax,
+                      OPT_RISCVLinkOptTable::no_riscv_relax, /*default=*/true));
 
   // --no-relax-zero
   if (ArgList.hasArg(OPT_RISCVLinkOptTable::no_relax_zero))

test/AArch64/standalone/TLS_GD_ALIGN/GDAlign.test

@@ -1,7 +1,7 @@
 #---GDAlign.test----------------------------------------------------------#
 # Check that TLS GD GOT entries account for TLS block alignment padding.
 RUN: %clang %clangopts -target aarch64 -c %p/Inputs/gd-align.c -o %t.o -fPIC -ftls-model=global-dynamic
-RUN: %link %linkopts -march aarch64 %t.o -o %t.out --no-threads
+RUN: %link %linkopts -march aarch64 %t.o -o %t.out --thread-count=1
 RUN: %readelf -x .got %t.out | %filecheck %s
 
 CHECK: .got

test/AArch64/standalone/TLS_IE_ALIGN/IEAlign.test

@@ -1,7 +1,7 @@
 #---IEAlign.test----------------------------------------------------------#
 # Check that TLS IE GOT entries account for TLS block alignment padding.
 RUN: %clang %clangopts -target aarch64 -c %p/Inputs/ie-align.c -o %t.o -fPIC -ftls-model=initial-exec
-RUN: %link %linkopts -march aarch64 %t.o -o %t.out --no-threads
+RUN: %link %linkopts -march aarch64 %t.o -o %t.out --thread-count=1
 RUN: %readelf -x .got %t.out | %filecheck %s
 
 CHECK: .got

test/AArch64/standalone/TLS_IE_GOT_Offsets/TLS_IE_GOT_Offsets.test

@@ -13,7 +13,7 @@
 
 RUN: %clang %clangopts -target aarch64 -c %p/Inputs/hw1.c -o %t.o \
 RUN: -fPIC -ftls-model=initial-exec -fdata-sections
-RUN: %link %linkopts -march aarch64 %t.o -o %t.out --no-threads
+RUN: %link %linkopts -march aarch64 %t.o -o %t.out --thread-count=1
 RUN: %readelf -x .got %t.out | %filecheck %s
 
 # The .got section should contain two TLS IE entries with offsets 0x10 and 0x14

test/Common/standalone/FlagOverwrite/FlagOverwrite.test

@@ -0,0 +1,27 @@
+#---FlagOverwrite.test--------------------- Executable --------------------#
+UNSUPPORTED: x86
+#BEGIN_COMMENT
+# Check that the last option is the one being used for mutually exclusive flags.
+#END_COMMENT
+#START_TEST
+RUN: %clang %clangopts -ffunction-sections -c %p/Inputs/1.cpp -o %t1.o
+RUN: %link -o %t1.out -shared -z=notext %t1.o --no-warn-shared-textrel --warn-shared-textrel 2>&1 | %filecheck %s -check-prefix=TEXTREL
+RUN: %link -o %t1.out -shared -z=notext %t1.o --warn-shared-textrel --no-warn-shared-textrel 2>&1 | %filecheck %s -check-prefix=NOTEXTREL -allow-empty
+RUN: %not %link -o %t1.out -shared -z=notext %t1.o --warn-shared-textrel --no-fatal-warnings --fatal-warnings 2>&1 | %filecheck %s -check-prefix=FATAL
+RUN: %link -o %t1.out -shared -z=notext %t1.o --warn-shared-textrel --fatal-warnings --no-fatal-warnings 2>&1 | %filecheck %s -check-prefix=NOFATAL
+RUN: %link %linkopts -o %t1.out %t1.o --verbose --no-demangle --demangle 2>&1 | %filecheck %s -check-prefix=DEMANGLE
+RUN: %link %linkopts -o %t1.out %t1.o --verbose --demangle --no-demangle 2>&1 | %filecheck %s -check-prefix=NODEMANGLE
+RUN: %link %linkopts -o %t1.out %t1.o --no-omagic --omagic -z max-page-size=0x1000
+RUN: %readelf --elf-output-style LLVM -l -W %t1.out 2>&1 | %filecheck %s -check-prefix=OMAGIC
+RUN: %link %linkopts -o %t1.out %t1.o --omagic -z max-page-size=0x1000 --no-omagic
+RUN: %readelf --elf-output-style LLVM -l -W %t1.out 2>&1 | %filecheck %s -check-prefix=NOOMAGIC
+
+TEXTREL: Warning: Add DT_TEXTREL in a shared object!
+NOTEXTREL-NOT: Warning: Add DT_TEXTREL in a shared object!
+FATAL: Fatal: Linking had errors.
+NOFATAL-NOT: Fatal: Linking had errors.
+DEMANGLE: Verbose: Adding symbol foo()
+NODEMANGLE: Verbose: Adding symbol _Z3foov
+OMAGIC-NOT: 4096
+NOOMAGIC: 4096
+#END_TEST

test/Common/standalone/FlagOverwrite/Inputs/1.cpp

@@ -0,0 +1 @@
+int foo() { return 0; }

test/RISCV/standalone/FlagOverwrite/FlagOverwrite.test

@@ -0,0 +1,16 @@
+#---FlagOverwrite.test--------------------- Executable------------------#
+#BEGIN_COMMENT
+# Check that the last option is the one being used for mutually exclusive flags.
+# Currently, it checks for:
+#    --[no-]relax
+#END_COMMENT
+#START_TEST
+RUN: %clang %clangopts -c %p/Inputs/1.s -o %t1.1.o
+RUN: %link %linkopts --emit-relocs --no-relax --relax  -T %p/Inputs/script.t  %t1.1.o -o %t1.out
+RUN: %objdump --no-print-imm-hex -d %t1.out |  %filecheck %s -check-prefix=RELAX
+RUN: %link %linkopts --emit-relocs --relax --no-relax  -T %p/Inputs/script.t  %t1.1.o -o %t1.out
+RUN: %objdump --no-print-imm-hex -d %t1.out |  %filecheck %s -check-prefix=NORELAX
+
+RELAX-NOT: auipc	ra, 0
+NORELAX: auipc	ra, 0
+#END_TEST

test/RISCV/standalone/FlagOverwrite/Inputs/1.s

@@ -0,0 +1,20 @@
+.section .text.foo
+.globl foo
+.type foo, @function
+foo:
+	lui	a5,%hi(bar)
+	lw	a5,%lo(bar)(a5)
+	beqz	a5,.L4
+	call	baz
+.L4:
+	nop
+
+.section .text.baz
+.globl baz
+.type baz, @function
+baz:
+  nop
+.data
+.globl bar
+bar:
+ .word 1

test/RISCV/standalone/FlagOverwrite/Inputs/script.t

@@ -0,0 +1,9 @@
+SECTIONS {
+  .text (0x1233000) : {
+    *(.text.foo)
+    *(.text.baz)
+  }
+  .data (0x12345600) : {
+  *(.data)
+  }
+}