Reapply [test] [llvm-config] Assume unix style lib names on mingw targets

Assume the MSVC style naming only for "windows-msvc" targets.

After the previous attempt, this was changed to use the host triple
instead of the target.

Differential Revision: https://reviews.llvm.org/D149998

Author: mstorsjo

llvm/test/lit.cfg.py

@@ -365,6 +365,10 @@ def have_cxx_shared_library():
     if not config.target_triple.startswith(("nvptx", "xcore")):
         config.available_features.add('object-emission')
 
+# Allow checking for specific details in the host triple
+if config.host_triple:
+    config.available_features.add('host=%s' % config.host_triple)
+
 if config.have_llvm_driver:
   config.available_features.add('llvm-driver')
 

llvm/test/tools/llvm-config/system-libs.test

@@ -1,6 +1,6 @@
 RUN: llvm-config --link-static --system-libs Support 2>&1 | FileCheck %s
 REQUIRES: static-libs
-UNSUPPORTED: system-windows
+UNSUPPORTED: host={{.*-windows-msvc}}
 CHECK: -l
 CHECK-NOT: error
 CHECK-NOT: warning

llvm/test/tools/llvm-config/system-libs.windows.test

@@ -1,6 +1,6 @@
 RUN: llvm-config --link-static --system-libs Support 2>&1 | FileCheck %s
 REQUIRES: static-libs
-REQUIRES: system-windows
+REQUIRES: host={{.*-windows-msvc}}
 CHECK-NOT: -l
 CHECK: psapi.lib shell32.lib ole32.lib uuid.lib advapi32.lib
 CHECK-NOT: error