[flang-commits] [flang] [flang][debug] Add accurate line number information to module. (PR #214011)

[Abid Qadeer via flang-commits]

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@@ -0,0 +1,44 @@
+// RUN: fir-opt --add-debug-info --mlir-print-debuginfo %s | FileCheck %s
+
+// The line of a DIModuleAttr comes from the location of the module's
+// `fir.module_debug_imports`, which is that of the MODULE statement. Without
+// one, it falls back to a guess based on the first member of the module.
+
+module {
+  // A module whose MODULE statement is on line 4, well before its first
+  // member on line 20. The region is empty because the module has no USE.
+  fir.module_debug_imports "no_use" {
+  } loc(#loc_no_use)
+  fir.global @_QMno_useEx : i32 {
+    %0 = fir.zero_bits i32
+    fir.has_value %0 : i32
+  } loc(#loc_x)
+
+  // Same, but with a USE statement in the region.
+  fir.module_debug_imports "with_use" {
+    fir.use_stmt "no_use"
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abidh wrote:

  That indeed looks confusing. I have fixed it now by introducing `other_mod` here.

https://github.com/llvm/llvm-project/pull/214011