[MSVC/Fortran] Add /Fd flag when /Zi or /ZI flags are detected

Fixes #1731

waflib/extras/msvc_pdb.py

@@ -0,0 +1,45 @@
+#!/usr/bin/env python
+# encoding: utf-8
+# Rafaël Kooi 2019
+
+from waflib import TaskGen, Tools
+@TaskGen.feature('c', 'cxx', 'fc')
+@TaskGen.after_method('propagate_uselib_vars')
+def add_pdb_per_object(self):
+    """For msvc/fortran, specify a unique compile pdb per object, to work
+    around LNK4099. Flags are updated with a unique /Fd flag based on the
+    task output name. This is separate from the link pdb.
+    """
+
+    link_task = getattr(self, 'link_task', None)
+
+    for task in self.compiled_tasks:
+        node = task.outputs[0].change_ext('.pdb')
+        pdb_flag = '/Fd:' + node.abspath()
+
+        canAddNode = False
+        for flagname in ('CFLAGS', 'CXXFLAGS', 'FCFLAGS'):
+            if not flagname in task.env:
+                continue
+
+            flags = task.env[flagname]
+
+            for i, flag in reversed(list(enumerate(flags))):
+                # Capture both /Zi and /ZI, which cause the compiler to emit a PDB file.
+                if flag[1:].lower() == 'zi':
+                    canAddNode = True
+                    task.env.append_unique(flagname, pdb_flag)
+
+                # Strip existing /Fd, /FS, or /MP flags.
+                # We have to check for /Fd case sensitive, so that we won't accidentally
+                # overwrite GCC flags such as "-fdata-sections".
+                if flag[1:3] == 'Fd' \
+                or flag[1:].lower() == 'fs' \
+                or flag[1:].lower() == 'mp':
+                    del task.env[flagname][i]
+
+        if canAddNode:
+            if link_task and not node in link_task.dep_nodes:
+                link_task.dep_nodes.append(node)
+            if not node in task.outputs:
+                task.outputs.append(node)