[clang] [clang][DependencyScanner] Remove all warning flags when suppressing warnings (PR #71612)

[Michael Spencer via cfe-commits]

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@@ -0,0 +1,84 @@
+// RUN: rm -rf %t
+// RUN: split-file %s %t
+// RUN: sed -e "s|DIR|%/t|g" %t/build/compile-commands.json.in > %t/build/compile-commands.json
+// RUN: clang-scan-deps -compilation-database %t/build/compile-commands.json \
+// RUN:   -j 1 -format experimental-full -optimize-args=system-warnings > %t/deps.db
+// RUN: cat %t/deps.db | sed 's:\\\\\?:/:g' | FileCheck %s -DPREFIX=%/t
+
+// CHECK:      {
+// CHECK-NEXT:   "modules": [
+// CHECK-NEXT:     {
+// CHECK-NEXT:       "clang-module-deps": [],
+// CHECK-NEXT:       "clang-modulemap-file":
+// CHECK-NEXT:       "command-line": [
+// CHECK-NOT:          "-W
+// CHECK:            ],
+// CHECK-NEXT:       "context-hash": "{{.*}}",
+// CHECK-NEXT:       "file-deps": [
+// CHECK:            ],
+// CHECK-NEXT:       "name": "A"
+// CHECK-NEXT:     },
+// CHECK-NEXT:     {
+// CHECK-NEXT:       "clang-module-deps": [],
+// CHECK-NEXT:       "clang-modulemap-file":
+// CHECK-NEXT:       "command-line": [
+// CHECK-NOT:          "-W
+// CHECK:            ],
+// CHECK-NEXT:       "context-hash": "{{.*}}",
+// CHECK-NEXT:       "file-deps": [
+// CHECK:            ],
+// CHECK-NEXT:       "name": "B"
+// CHECK-NEXT:     }
+// CHECK-NEXT:   ],
+// CHECK-NEXT:   "translation-units": [
+// CHECK:        ]
+// CHECK:      }
+
+//--- build/compile-commands.json.in
+
+[
+{
+  "directory": "DIR",
+  "command": "clang -c DIR/A.m -isystem modules/A -I modules/B -fmodules -fmodules-cache-path=DIR/module-cache -fimplicit-module-maps",
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Bigcheese wrote:

Ah, I missed the `-isystem`. It's verifying that both `-isystem` and `[system]` work.

https://github.com/llvm/llvm-project/pull/71612