Merge pull request #684 from mesonbuild/pdb

Create pdb files with MSVC

mesonbuild/backend/backends.py

@@ -120,6 +120,12 @@ def get_target_filename_for_linking(self, target):
             return os.path.join(self.get_target_dir(target), target.get_filename())
         raise AssertionError('BUG: Tried to link to something that\'s not a library')
 
+    def get_target_debug_filename(self, target):
+        fname = target.get_debug_filename()
+        if not fname:
+            raise AssertionError("BUG: Tried to generate debug filename when it doesn't exist")
+        return os.path.join(self.get_target_dir(target), fname)
+
     def get_target_dir(self, target):
         if self.environment.coredata.get_builtin_option('layout') == 'mirror':
             dirname = target.get_subdir()

mesonbuild/backend/ninjabackend.py

@@ -544,6 +544,13 @@ def generate_target_install(self, d):
                 else:
                     # XXX: Add BuildTarget-specific install dir cases here
                     outdir = self.environment.get_libdir()
+                if isinstance(t, build.SharedLibrary) or isinstance(t, build.Executable):
+                    if t.get_debug_filename():
+                        # Install the debug symbols file in the same place as
+                        # the target itself. It has no aliases, should not be
+                        # stripped, and doesn't have an install_rpath
+                        i = [self.get_target_debug_filename(t), outdir, [], False, '']
+                        d.targets.append(i)
                 i = [self.get_target_filename(t), outdir, t.get_aliaslist(),\
                     should_strip, t.install_rpath]
                 d.targets.append(i)
@@ -1482,6 +1489,66 @@ def get_cross_stdlib_args(self, target, compiler):
             return []
         return compiler.get_no_stdinc_args()
 
+    def get_compile_debugfile_args(self, compiler, target, objfile):
+        if compiler.id != 'msvc':
+            return []
+        # The way MSVC uses PDB files is documented exactly nowhere so
+        # the following is what we have been able to decipher via
+        # reverse engineering.
+        #
+        # Each object file gets the path of its PDB file written
+        # inside it.  This can be either the final PDB (for, say,
+        # foo.exe) or an object pdb (for foo.obj). If the former, then
+        # each compilation step locks the pdb file for writing, which
+        # is a bottleneck and object files from one target can not be
+        # used in a different target. The latter seems to be the
+        # sensible one (and what Unix does) but there is a catch.  If
+        # you try to use precompiled headers MSVC will error out
+        # because both source and pch pdbs go in the same file and
+        # they must be the same.
+        #
+        # This means:
+        #
+        # - pch files must be compiled anew for every object file (negating
+        #   the entire point of having them in the first place)
+        # - when using pch, output must go to the target pdb
+        #
+        # Since both of these are broken in some way, use the one that
+        # works for each target. This unfortunately means that you
+        # can't combine pch and object extraction in a single target.
+        #
+        # PDB files also lead to filename collisions. A target foo.exe
+        # has a corresponding foo.pdb. A shared library foo.dll _also_
+        # has pdb file called foo.pdb. So will a static library
+        # foo.lib, which clobbers both foo.pdb _and_ the dll file's
+        # export library called foo.lib (by default, currently we name
+        # them libfoo.a to avoidt this issue). You can give the files
+        # unique names such as foo_exe.pdb but VC also generates a
+        # bunch of other files which take their names from the target
+        # basename (i.e. "foo") and stomp on each other.
+        #
+        # CMake solves this problem by doing two things. First of all
+        # static libraries do not generate pdb files at
+        # all. Presumably you don't need them and VC is smart enough
+        # to look up the original data when linking (speculation, not
+        # tested). The second solution is that you can only have
+        # target named "foo" as an exe, shared lib _or_ static
+        # lib. This makes filename collisions not happen. The downside
+        # is that you can't have an executable foo that uses a shared
+        # library libfoo.so, which is a common idiom on Unix.
+        #
+        # If you feel that the above is completely wrong and all of
+        # this is actually doable, please send patches.
+
+        if target.has_pch():
+            tfilename = self.get_target_filename_abs(target)
+            return compiler.get_compile_debugfile_args(tfilename)
+        else:
+            return compiler.get_compile_debugfile_args(objfile)
+
+    def get_link_debugfile_args(self, linker, target, outname):
+        return linker.get_link_debugfile_args(outname)
+
     def generate_single_compile(self, target, outfile, src, is_generated=False, header_deps=[], order_deps=[]):
         if(isinstance(src, str) and src.endswith('.h')):
             raise RuntimeError('Fug')
@@ -1568,6 +1635,8 @@ def generate_single_compile(self, target, outfile, src, is_generated=False, head
             commands+= compiler.get_include_args(i, False)
         if self.environment.coredata.base_options.get('b_pch', False):
             commands += self.get_pch_include_args(compiler, target)
+
+        commands += self.get_compile_debugfile_args(compiler, target, rel_obj)
         crstr = ''
         if target.is_cross:
             crstr = '_CROSS'
@@ -1636,6 +1705,7 @@ def generate_msvc_pch_command(self, target, compiler, pch):
         just_name = os.path.split(header)[1]
         (objname, pch_args) = compiler.gen_pch_args(just_name, source, dst)
         commands += pch_args
+        commands += self.get_compile_debugfile_args(compiler, target, objname)
         dep = dst + '.' + compiler.get_depfile_suffix()
         return (commands, dep, dst, [objname])
 
@@ -1715,6 +1785,7 @@ def generate_link(self, target, outfile, outname, obj_list, linker, extra_args=[
                                                      linker)
         commands += linker.get_buildtype_linker_args(self.environment.coredata.get_builtin_option('buildtype'))
         commands += linker.get_option_link_args(self.environment.coredata.compiler_options)
+        commands += self.get_link_debugfile_args(linker, target, outname)
         if not(isinstance(target, build.StaticLibrary)):
             commands += self.environment.coredata.external_link_args[linker.get_language()]
         if isinstance(target, build.Executable):

mesonbuild/build.py

@@ -206,6 +206,8 @@ def __init__(self, name, subdir, subproject, is_cross, sources, objects, environ
         self.link_targets = []
         self.link_depends = []
         self.filename = 'no_name'
+        # The file with debugging symbols
+        self.debug_filename = None
         self.need_install = False
         self.pch = {}
         self.extra_args = {}
@@ -467,6 +469,15 @@ def get_subdir(self):
     def get_filename(self):
         return self.filename
 
+    def get_debug_filename(self):
+        """
+        The name of the file that contains debugging symbols for this target
+
+        Returns None if there are no debugging symbols or if they are embedded
+        in the filename itself
+        """
+        return self.debug_filename
+
     def get_extra_args(self, language):
         return self.extra_args.get(language, [])
 
@@ -729,6 +740,11 @@ def __init__(self, name, subdir, subproject, is_cross, sources, objects, environ
         self.filename = self.name
         if self.suffix:
             self.filename += '.' + self.suffix
+        # See determine_debug_filenames() in build.SharedLibrary
+        buildtype = environment.coredata.get_builtin_option('buildtype')
+        if compiler_is_msvc(self.sources, is_cross, environment) and \
+           buildtype.startswith('debug'):
+            self.debug_filename = self.prefix + self.name + '.pdb'
 
     def type_suffix(self):
         return "@exe"
@@ -754,6 +770,11 @@ def __init__(self, name, subdir, subproject, is_cross, sources, objects, environ
             else:
                 self.suffix = 'a'
         self.filename = self.prefix + self.name + '.' + self.suffix
+        # See determine_debug_filenames() in build.SharedLibrary
+        buildtype = environment.coredata.get_builtin_option('buildtype')
+        if compiler_is_msvc(self.sources, is_cross, environment) and \
+           buildtype.startswith('debug'):
+            self.debug_filename = self.prefix + self.name + '.pdb'
 
     def type_suffix(self):
         return "@sta"
@@ -776,6 +797,7 @@ def __init__(self, name, subdir, subproject, is_cross, sources, objects, environ
             self.suffix = None
         self.basic_filename_tpl = '{0.prefix}{0.name}.{0.suffix}'
         self.determine_filenames(is_cross, environment)
+        self.determine_debug_filenames(is_cross, environment)
 
     def determine_filenames(self, is_cross, env):
         """
@@ -865,6 +887,21 @@ def determine_filenames(self, is_cross, env):
             self.suffix = suffix
         self.filename = self.filename_tpl.format(self)
 
+    def determine_debug_filenames(self, is_cross, env):
+        """
+        Determine the debug filename(s) using the prefix/name/etc detected in
+        determine_filenames() above.
+        """
+        buildtype = env.coredata.get_builtin_option('buildtype')
+        if compiler_is_msvc(self.sources, is_cross, env) and buildtype.startswith('debug'):
+            # Currently we only implement separate debug symbol files for MSVC
+            # since the toolchain does it for us. Other toolchains embed the
+            # debugging symbols in the file itself by default.
+            if self.soversion:
+                self.debug_filename = '{0.prefix}{0.name}-{0.soversion}.pdb'.format(self)
+            else:
+                self.debug_filename = '{0.prefix}{0.name}.pdb'.format(self)
+
     def process_kwargs(self, kwargs, environment):
         super().process_kwargs(kwargs, environment)
         # Shared library version

mesonbuild/compilers.py

@@ -373,6 +373,14 @@ def get_cross_extra_flags(self, environment, *, compile, link):
     def get_colorout_args(self, colortype):
         return []
 
+    # Some compilers (msvc) write debug info to a separate file.
+    # These args specify where it should be written.
+    def get_compile_debugfile_args(self, rel_obj):
+        return []
+
+    def get_link_debugfile_args(self, rel_obj):
+        return []
+
 class CCompiler(Compiler):
     def __init__(self, exelist, version, is_cross, exe_wrapper=None):
         super().__init__(exelist, version)
@@ -1708,16 +1716,11 @@ def unix_compile_flags_to_native(self, args):
 class VisualStudioCCompiler(CCompiler):
     std_warn_args = ['/W3']
     std_opt_args= ['/O2']
-    vs2010_always_args = ['/nologo', '/showIncludes']
-    vs2013_always_args = ['/nologo', '/showIncludes', '/FS']
 
     def __init__(self, exelist, version, is_cross, exe_wrap):
         CCompiler.__init__(self, exelist, version, is_cross, exe_wrap)
         self.id = 'msvc'
-        if int(version.split('.')[0]) > 17:
-            self.always_args = VisualStudioCCompiler.vs2013_always_args
-        else:
-            self.always_args = VisualStudioCCompiler.vs2010_always_args
+        self.always_args = ['/nologo', '/showIncludes']
         self.warn_args = {'1': ['/W2'],
                           '2': ['/W3'],
                           '3': ['/w4']}
@@ -1878,6 +1881,16 @@ def has_argument(self, arg, env):
             raise MesonException('Compiling test app failed.')
         return not(warning_text in stde or warning_text in stdo)
 
+    def get_compile_debugfile_args(self, rel_obj):
+        pdbarr = rel_obj.split('.')[:-1]
+        pdbarr += ['pdb']
+        return ['/Fd' + '.'.join(pdbarr)]
+
+    def get_link_debugfile_args(self, targetfile):
+        pdbarr = targetfile.split('.')[:-1]
+        pdbarr += ['pdb']
+        return ['/DEBUG', '/PDB:' + '.'.join(pdbarr)]
+
 class VisualStudioCPPCompiler(VisualStudioCCompiler):
     def __init__(self, exelist, version, is_cross, exe_wrap):
         VisualStudioCCompiler.__init__(self, exelist, version, is_cross, exe_wrap)
@@ -2564,6 +2577,11 @@ def unix_link_flags_to_native(self, args):
     def unix_compile_flags_to_native(self, args):
         return args[:]
 
+    def get_link_debugfile_args(self, targetfile):
+        pdbarr = targetfile.split('.')[:-1]
+        pdbarr += ['pdb']
+        return ['/DEBUG', '/PDB:' + '.'.join(pdbarr)]
+
 class ArLinker():
 
     def __init__(self, exelist):
@@ -2612,3 +2630,6 @@ def unix_link_flags_to_native(self, args):
 
     def unix_compile_flags_to_native(self, args):
         return args[:]
+
+    def get_link_debugfile_args(self, targetfile):
+        return []

run_tests.py

@@ -169,7 +169,7 @@ def validate_install(srcdir, installdir):
     # Check if there are any unexpected files
     found = get_relative_files_list_from_dir(installdir)
     for fname in found:
-        if fname not in expected:
+        if fname not in expected and not fname.endswith('.pdb'):
             ret_msg += 'Extra file {0} found.\n'.format(fname)
     return ret_msg
 

test cases/common/86 same basename/meson.build

@@ -1,13 +1,11 @@
 project('same basename', 'c')
 
+subdir('sharedsub')
+subdir('staticsub')
+
 # Use the same source file to check that each top level target
 # has its own unique working directory. If they don't
 # then the .o files will clobber each other.
-shlib = shared_library('name', 'lib.c', c_args : '-DSHAR')
-
-# On Windows a static lib is now libfoo.a, so it does not conflict with foo.lib
-# from the shared library above
-stlib = static_library('name', 'lib.c', c_args : '-DSTAT')
 
 exe1 = executable('name', 'exe1.c', link_with : stlib)
 exe2 = executable('name2', 'exe2.c', link_with : shlib)

test cases/common/86 same basename/sharedsub/meson.build

@@ -0,0 +1 @@
+shlib = shared_library('name', '../lib.c', c_args : '-DSHAR')

test cases/common/86 same basename/staticsub/meson.build

@@ -0,0 +1,3 @@
+# On Windows a static lib is now libfoo.a, so it does not conflict with foo.lib
+# from the shared library above
+stlib = static_library('name', '../lib.c', c_args : '-DSTAT')