Extend the C++ module scanner to handle Fortran, too.fortranmodscan

2 files changed, 106 insertions, 44 deletions

diff --git a/mesonbuild/backend/ninjabackend.py b/mesonbuild/backend/ninjabackend.py
index 71deab0..6c60958 100644
--- a/mesonbuild/backend/ninjabackend.py
+++ b/mesonbuild/backend/ninjabackend.py
@@ -872,7 +872,11 @@ int dummy;
         self.generate_shlib_aliases(target, self.get_target_dir(target))
         self.add_build(elem)
 
-    def should_scan_target(self, target):
+    def should_use_dyndeps_for_target(self, target):
+        if mesonlib.version_compare(self.ninja_version, '<1.10.0'):
+            return False
+        if 'fortran' in target.compilers:
+            return True
         if 'cpp' not in target.compilers:
             return False
         # Currently only the preview version of Visual Studio is supported.
@@ -883,18 +887,16 @@ int dummy;
             return False
         if mesonlib.version_compare(cpp.version, '<19.28.28617'):
             return False
-        if mesonlib.version_compare(self.ninja_version, '<1.10.0'):
-            return False
         return True
 
     def generate_dependency_scan_target(self, target, compiled_sources, source2object):
-        if not self.should_scan_target(target):
+        if not self.should_use_dyndeps_for_target(target):
             return
         depscan_file = self.get_dep_scan_file_for(target)
         pickle_base = target.name + '.dat'
         pickle_file = os.path.join(self.get_target_private_dir(target), pickle_base).replace('\\', '/')
         pickle_abs = os.path.join(self.get_target_private_dir_abs(target), pickle_base).replace('\\', '/')
-        rule_name = 'cppscan'
+        rule_name = 'depscan'
         scan_sources = self.select_sources_to_scan(compiled_sources)
         elem = NinjaBuildElement(self.all_outputs, depscan_file, rule_name, scan_sources)
         elem.add_item('picklefile', pickle_file)
@@ -907,10 +909,15 @@ int dummy;
         # in practice pick up C++ and Fortran files. If some other language
         # requires scanning (possibly Java to deal with inner class files)
         # then add them here.
+        all_suffixes = set()
+        for s in compilers.lang_suffixes['cpp']:
+            all_suffixes.add(s)
+        for s in compilers.lang_suffixes['fortran']:
+            all_suffixes.add(s)
         selected_sources = []
         for source in compiled_sources:
             ext = os.path.splitext(source)[1][1:]
-            if ext in compilers.lang_suffixes['cpp']:
+            if ext in all_suffixes:
                 selected_sources.append(source)
         return selected_sources
 
@@ -1945,7 +1952,15 @@ int dummy;
         description = 'Compiling Swift source $in'
         self.add_rule(NinjaRule(rule, command, [], description))
 
-    def generate_fortran_dep_hack(self, crstr):
+    def use_dyndeps_for_fortran(self) -> bool:
+        '''Use the new Ninja feature for scanning dependencies during build,
+        rather than up front. Remove this and all old scanning code once Ninja
+        minimum version is bumped to 1.10.'''
+        return mesonlib.version_compare(self.ninja_version, '>=1.10.0')
+
+    def generate_fortran_dep_hack(self, crstr: str) -> None:
+        if self.use_dyndeps_for_fortran():
+            return
         rule = 'FORTRAN_DEP_HACK{}'.format(crstr)
         if mesonlib.is_windows():
             cmd = ['cmd', '/C']
@@ -2029,22 +2044,16 @@ https://gcc.gnu.org/bugzilla/show_bug.cgi?id=47485'''))
 
 
     def generate_scanner_rules(self):
-        scanner_languages = {'cpp'} # Fixme, add Fortran.
-        for for_machine in MachineChoice:
-            clist = self.environment.coredata.compilers[for_machine]
-            for langname, compiler in clist.items():
-                if langname not in scanner_languages:
-                    continue
-                rulename = '{}scan'.format(langname)
-                if rulename in self.ruledict:
-                    # Scanning command is the same for native and cross compilation.
-                    continue
-                command = self.environment.get_build_command() + \
-                    ['--internal', 'depscan']
-                args = ['$picklefile', '$out', '$in']
-                description = 'Module scanner for {}.'.format(langname)
-                rule = NinjaRule(rulename, command, args, description)
-                self.add_rule(rule)
+        rulename = 'depscan'
+        if rulename in self.ruledict:
+            # Scanning command is the same for native and cross compilation.
+            return
+        command = self.environment.get_build_command() + \
+            ['--internal', 'depscan']
+        args = ['$picklefile', '$out', '$in']
+        description = 'Module scanner.'
+        rule = NinjaRule(rulename, command, args, description)
+        self.add_rule(rule)
 
 
     def generate_compile_rules(self):
@@ -2146,6 +2155,8 @@ https://gcc.gnu.org/bugzilla/show_bug.cgi?id=47485'''))
         """
         Find all module and submodule made available in a Fortran code file.
         """
+        if self.use_dyndeps_for_fortran():
+            return
         compiler = None
         # TODO other compilers
         for lang, c in self.environment.coredata.compilers.host.items():
@@ -2198,6 +2209,8 @@ https://gcc.gnu.org/bugzilla/show_bug.cgi?id=47485'''))
         """
         Find all module and submodule needed by a Fortran target
         """
+        if self.use_dyndeps_for_fortran():
+            return []
 
         dirname = Path(self.get_target_private_dir(target))
         tdeps = self.fortran_deps[target.get_basename()]
@@ -2502,16 +2515,20 @@ https://gcc.gnu.org/bugzilla/show_bug.cgi?id=47485'''))
             if not is_generated:
                 abs_src = Path(build_dir) / rel_src
                 extra_deps += self.get_fortran_deps(compiler, abs_src, target)
-            # Dependency hack. Remove once multiple outputs in Ninja is fixed:
-            # https://groups.google.com/forum/#!topic/ninja-build/j-2RfBIOd_8
-            for modname, srcfile in self.fortran_deps[target.get_basename()].items():
-                modfile = os.path.join(self.get_target_private_dir(target),
-                                       compiler.module_name_to_filename(modname))
-
-                if srcfile == src:
-                    crstr = self.get_rule_suffix(target.for_machine)
-                    depelem = NinjaBuildElement(self.all_outputs, modfile, 'FORTRAN_DEP_HACK' + crstr, rel_obj)
-                    self.add_build(depelem)
+            if not self.use_dyndeps_for_fortran():
+                # Dependency hack. Remove once multiple outputs in Ninja is fixed:
+                # https://groups.google.com/forum/#!topic/ninja-build/j-2RfBIOd_8
+                for modname, srcfile in self.fortran_deps[target.get_basename()].items():
+                    modfile = os.path.join(self.get_target_private_dir(target),
+                                           compiler.module_name_to_filename(modname))
+
+                    if srcfile == src:
+                        crstr = self.get_rule_suffix(target.for_machine)
+                        depelem = NinjaBuildElement(self.all_outputs,
+                                                    modfile,
+                                                     'FORTRAN_DEP_HACK' + crstr,
+                                                      rel_obj)
+                        self.add_build(depelem)
             commands += compiler.get_module_outdir_args(self.get_target_private_dir(target))
 
         element = NinjaBuildElement(self.all_outputs, rel_obj, compiler_name, rel_src)
@@ -2537,7 +2554,7 @@ https://gcc.gnu.org/bugzilla/show_bug.cgi?id=47485'''))
         return (rel_obj, rel_src.replace('\\', '/'))
 
     def add_dependency_scanner_entries_to_element(self, target, compiler, element):
-        if not self.should_scan_target(target):
+        if not self.should_use_dyndeps_for_target(target):
             return
         dep_scan_file = self.get_dep_scan_file_for(target)
         element.add_item('dyndep', dep_scan_file)
diff --git a/mesonbuild/scripts/depscan.py b/mesonbuild/scripts/depscan.py
index 6eebbfe..24a1f36 100644
--- a/mesonbuild/scripts/depscan.py
+++ b/mesonbuild/scripts/depscan.py
@@ -15,12 +15,23 @@
 import pathlib
 import pickle
 import re
+import os
+import sys
 import typing as T
 
 from ..backend.ninjabackend import TargetDependencyScannerInfo
+from ..compilers.compilers import lang_suffixes
 
-import_re = re.compile('\w*import ([a-zA-Z0-9]+);')
-export_re = re.compile('\w*export module ([a-zA-Z0-9]+);')
+cpp_import_re = re.compile('\w*import ([a-zA-Z0-9]+);')
+cpp_export_re = re.compile('\w*export module ([a-zA-Z0-9]+);')
+
+FORTRAN_INCLUDE_PAT = r"^\s*#?include\s*['\"](\w+\.\w+)['\"]"
+FORTRAN_MODULE_PAT = r"^\s*\bmodule\b\s+(\w+)\s*(?:!+.*)*$"
+FORTRAN_SUBMOD_PAT = r"^\s*\bsubmodule\b\s*\((\w+:?\w+)\)\s*(\w+)"
+FORTRAN_USE_PAT = r"^\s*use,?\s*(?:non_intrinsic)?\s*(?:::)?\s*(\w+)"
+
+fortran_module_re = re.compile(FORTRAN_MODULE_PAT)
+fortran_use_re = re.compile(FORTRAN_USE_PAT)
 
 class DependencyScanner:
     def __init__(self, pickle_file: str, outfile: str, sources: T.List[str]):
@@ -34,9 +45,19 @@ class DependencyScanner:
         self.sources_with_exports = [] # type: T.List[str]
     
     def scan_file(self, fname: str) -> None:
-        for line in pathlib.Path(fname).read_text().split('\n'):
-            import_match = import_re.match(line)
-            export_match = export_re.match(line)
+        suffix = os.path.splitext(fname)[1][1:]
+        if suffix in lang_suffixes['fortran']:
+            self.scan_fortran_file(fname)
+        elif suffix in lang_suffixes['cpp']:
+            self.scan_fortran_file(fname)
+        else:
+            sys.exit('Can not scan files with suffix .{}.'.format(suffix))
+
+    def scan_fortran_file(self, fname: str) -> None:
+        fpath = pathlib.Path(fname)
+        for line in fpath.read_text().split('\n'):
+            import_match = fortran_use_re.match(line)
+            export_match = fortran_module_re.match(line)
             if import_match:
                 needed = import_match.group(1)
                 if fname in self.needs:
@@ -51,13 +72,37 @@ class DependencyScanner:
                 self.provided_by[exported_module] = fname
                 self.exports[fname] = exported_module
 
+    def scan_cpp_file(self, fname: str) -> None:
+        fpath = pathlib.Path(fname)
+        for line in fpath.read_text().split('\n'):
+            import_match = cpp_import_re.match(line)
+            export_match = cpp_export_re.match(line)
+            if import_match:
+                needed = import_match.group(1)
+                if fname in self.needs:
+                    self.needs[fname].append(needed)
+                else:
+                    self.needs[fname] = [needed]
+            if export_match:
+                exported_module = export_match.group(1)
+                if exported_module in self.provided_by:
+                    raise RuntimeError('Multiple files provide module {}.'.format(exported_module))
+                self.sources_with_exports.append(fname)
+                self.provided_by[exported_module] = fname
+                self.exports[fname] = exported_module
     def objname_for(self, src: str) -> str:
         objname = self.target_data.source2object[src]
         assert(isinstance(objname, str))
         return objname
 
-    def ifcname_for(self, src: str) -> str:
-        return '{}.ifc'.format(self.exports[src])
+    def module_name_for(self, src: str) -> str:
+        suffix= os.path.splitext(src)[1][1:]
+        if suffix in lang_suffixes['fortran']:
+            return os.path.join(self.target_data.private_dir, '{}.mod'.format(self.exports[src]))
+        elif suffix in lang_suffixes['cpp']:
+            return '{}.ifc'.format(self.exports[src])
+        else:
+            raise RuntimeError('Unreachable code.')
 
     def scan(self) -> int:
         for s in self.sources:
@@ -67,15 +112,15 @@ class DependencyScanner:
             for src in self.sources:
                 objfilename = self.objname_for(src)
                 if src in self.sources_with_exports:
-                    ifc_entry = '| ' + self.ifcname_for(src)
+                    ifc_entry = '| ' + self.module_name_for(src)
                 else:
                     ifc_entry = ''
                 if src in self.needs:
                     # FIXME, handle all sources, not just the first one
                     modname = self.needs[src][0]
                     provider_src = self.provided_by[modname]
-                    provider_ifc = self.ifcname_for(provider_src)
-                    mod_dep = '| ' + provider_ifc
+                    provider_modfile = self.module_name_for(provider_src)
+                    mod_dep = '| ' + provider_modfile
                 else:
                     mod_dep = ''
                 ofile.write('build {} {}: dyndep {}\n'.format(objfilename,