[AIX]: Fix option processing for -b

[etiotto]

Summary

Code added by D106688 has a problem. It passes the option -bxyz to the system linker as -b xyz xyz (duplication of the string 'xyz' is incorrect). This patch fixes that oversight.

[jsji]

Tests please?

[hubert.reinterpretcast]

clang/lib/Driver/ToolChains/CommonArgs.cpp

261

Can we move the OPT_b block above into the if-else chain after the OPT_z case? The else occurring after the comment strikes me as being very unfortunate code formatting.

[etiotto]

Adapting test for -b option processing on AIX

[etiotto]

Address code review comment.

[hubert.reinterpretcast]

LGTM; thanks!

[jsji]

LGTM, Thanks.

clang/test/Driver/Xlinker-args.c

26

It would be better if we can tested mixing other options like -z .

[etiotto]

clang/test/Driver/Xlinker-args.c

26

I think the test is adequate as it guarantees options passed via "-b" are not going to be duplicated (which is the problem this PR addresses).

[jsji]

clang/test/Driver/Xlinker-args.c

26

Yes, it is testing what it tries to fix. However, it does NOT test what it *might* break. This is somehow similar to last patch, it does test what it wants -- passing down the option, but it did not test whether it pass more than needed.

The fix changes code related to handling of -z, so there is some risk of breaking -z, adding tests will ensure that the fix is good enough, and also prevent future regressions.

But yeah, as I said it is *better* to do that, not a must, depending on the quality level.

clang/lib/Driver/ToolChains/CommonArgs.cpp

for (const auto &II : Inputs) {
     if (II.isFilename()) {
       CmdArgs.push_back(II.getFilename());
       continue;
     }
 
     // Otherwise, this is a linker input argument.
     const Arg &A = II.getInputArg();
 
-    if (A.getOption().matches(options::OPT_b)) {
-      const llvm::Triple &T = TC.getTriple();
-      if (!T.isOSAIX()) {
-        TC.getDriver().Diag(diag::err_drv_unsupported_opt_for_target)
-          << A.getSpelling() << T.str();
-      }
-      // Pass -b prefix for AIX linker.
-      A.claim();
-      A.render(Args, CmdArgs);
-    }
     // Handle reserved library options.
     if (A.getOption().matches(options::OPT_Z_reserved_lib_stdcxx))
       TC.AddCXXStdlibLibArgs(Args, CmdArgs);
     else if (A.getOption().matches(options::OPT_Z_reserved_lib_cckext))
       TC.AddCCKextLibArgs(Args, CmdArgs);
     else if (A.getOption().matches(options::OPT_z)) {
       // Pass -z prefix for gcc linker compatibility.
       A.claim();
       A.render(Args, CmdArgs);
+    } else if (A.getOption().matches(options::OPT_b)) {
+      const llvm::Triple &T = TC.getTriple();
+      if (!T.isOSAIX()) {
+        TC.getDriver().Diag(diag::err_drv_unsupported_opt_for_target)
+            << A.getSpelling() << T.str();
+      }
+      // Pass -b prefix for AIX linker.
+      A.claim();
+      A.render(Args, CmdArgs);
     } else {
       A.renderAsInput(Args, CmdArgs);
     }
   }
 }
 
 void tools::addLinkerCompressDebugSectionsOption(
     const ToolChain &TC, const llvm::opt::ArgList &Args,

clang/test/Driver/Xlinker-args.c

 // Check that we extract --no-demangle from '-Xlinker' and '-Wl,', since that
 // was a collect2 argument.
 
 // RUN: %clang -target i386-apple-darwin9 -### \
 // RUN:   -Xlinker one -Xlinker --no-demangle \
 // RUN:   -Wl,two,--no-demangle,three -Xlinker four -z five -r %s 2> %t
 // RUN: FileCheck -check-prefix=DARWIN < %t %s
 
 /// -T is reordered to the last to make sure -L takes precedence.
 // RUN: %clang -target x86_64-pc-linux-gnu -### \
 // RUN:   -e _start -T a.lds -Xlinker one -Xlinker --no-demangle \
 // RUN:   -Wl,two,--no-demangle,three -Xlinker four -z five -r %s 2> %t
 // RUN: FileCheck -check-prefix=LINUX < %t %s
 
 // RUN: %clang -target powerpc-unknown-aix -### \
-// RUN:   -b one %s 2> %t
+// RUN:   -b one -b two %s 2> %t
 // RUN: FileCheck -check-prefix=AIX < %t %s
 
 // RUN: %clang -target powerpc-unknown-linux -### \
 // RUN:   -b one %s 2> %t
 // RUN: FileCheck -check-prefix=NOT-AIX < %t %s
 
 // DARWIN-NOT: --no-demangle
 // DARWIN: "one" "two" "three" "four" "-z" "five" "-r"
 // LINUX: "--no-demangle" "-e" "_start" "one" "two" "three" "four" "-z" "five" "-r" {{.*}} "-T" "a.lds"
-// AIX: "-b" "one" 
+// AIX: "-b" "one" "-b" "two"
 // NOT-AIX: error: unsupported option '-b' for target 'powerpc-unknown-linux'
 
 // Check that we forward '-Xlinker' and '-Wl,' on Windows.
 // RUN: %clang -target i686-pc-win32 -fuse-ld=link -### \
 // RUN:   -Xlinker one -Wl,two %s 2>&1 | \
 // RUN:   FileCheck -check-prefix=WIN %s
 // WIN: link.exe
 // WIN: "one"
 // WIN: "two"