Index: clang/lib/Driver/ToolChains/Gnu.cpp
===================================================================
--- clang/lib/Driver/ToolChains/Gnu.cpp
+++ clang/lib/Driver/ToolChains/Gnu.cpp
@@ -2088,6 +2088,7 @@
   TripleNoVendor = TargetTriple.getArchName().str() + "-" +
                    TargetTriple.getOSAndEnvironmentName().str();
   StringRef TripleNoVendorRef(TripleNoVendor);
+  StringRef TripleArg;
 
   // If --gcc-install-dir= is specified, skip filesystem detection.
   if (const Arg *A =
@@ -2156,6 +2157,9 @@
       return;
   }
 
+  if (const Arg *A = Args.getLastArg(options::OPT_target))
+    TripleArg = A->getValue();
+
   // Loop over the various components which exist and select the best GCC
   // installation available. GCC installs are ranked by version number.
   const GCCVersion VersionZero = GCCVersion::Parse("0.0.0");
@@ -2171,6 +2175,10 @@
       // Maybe filter out <libdir>/gcc and <libdir>/gcc-cross.
       bool GCCDirExists = VFS.exists(LibDir + "/gcc");
       bool GCCCrossDirExists = VFS.exists(LibDir + "/gcc-cross");
+      // Try to match the exact target triple passed by -target option.
+      if (TripleArg.size() > 1)
+        ScanLibDirForGCCTriple(TargetTriple, Args, LibDir, TripleArg, false,
+                               GCCDirExists, GCCCrossDirExists);
       // Try to match the exact target triple first.
       ScanLibDirForGCCTriple(TargetTriple, Args, LibDir, TargetTriple.str(),
                              false, GCCDirExists, GCCCrossDirExists);
Index: clang/test/Driver/cross-linux.c
===================================================================
--- clang/test/Driver/cross-linux.c
+++ clang/test/Driver/cross-linux.c
@@ -25,9 +25,15 @@
 // RUN: %clang -### -o %t %s 2>&1 -no-integrated-as -fuse-ld=ld \
 // RUN:   --gcc-toolchain=%S/Inputs/basic_cross_linux_tree/usr \
 // RUN:   --target=x86_64-unknown-linux-gnu -m32 \
-// RUN:   | FileCheck --check-prefix=CHECK-I386 %s
+// RUN:   | FileCheck --check-prefix=CHECK-X86-64-M32 %s
+// CHECK-X86-64-M32: "-cc1" "-triple" "i386-unknown-linux-gnu"
+// CHECK-X86-64-M32: "{{.*}}/Inputs/basic_cross_linux_tree/usr/lib/gcc/x86_64-unknown-linux-gnu/10.2.0/../../../../x86_64-unknown-linux-gnu/bin{{/|\\\\}}as" "--32"
+// CHECK-X96-64-M32: "{{.*}}/Inputs/basic_cross_linux_tree/usr/lib/gcc/x86_64-unknown-linux-gnu/10.2.0/../../../../x86_64-unknown-linux-gnu/bin{{/|\\\\}}ld" {{.*}} "-m" "elf_i386"
 //
 // RUN: %clang -### -o %t %s 2>&1 -no-integrated-as -fuse-ld=ld \
 // RUN:   --gcc-toolchain=%S/Inputs/basic_cross_linux_tree/usr \
 // RUN:   --target=i386-unknown-linux-gnu -m64 \
-// RUN:   | FileCheck --check-prefix=CHECK-X86-64 %s
+// RUN:   | FileCheck --check-prefix=CHECK-I386-M64 %s
+// CHECK-I386-M64: "-cc1" "-triple" "x86_64-unknown-linux-gnu"
+// CHECK-I386-M64: "{{.*}}/Inputs/basic_cross_linux_tree/usr/lib/gcc/i386-unknown-linux-gnu/10.2.0/../../../../i386-unknown-linux-gnu/bin{{/|\\\\}}as" "--64"
+// CHECK-I386-M64: "{{.*}}/Inputs/basic_cross_linux_tree/usr/lib/gcc/i386-unknown-linux-gnu/10.2.0/../../../../i386-unknown-linux-gnu/bin{{/|\\\\}}ld" {{.*}} "-m" "elf_x86_64"