From d648f3497ef9171379dd9cfe6c378351682597f8 Mon Sep 17 00:00:00 2001
From: David Seifert <soap@gentoo.org>
Date: Sun, 18 Jul 2021 23:14:36 +0200
Subject: [PATCH] Cuda: Filter -isystem with system paths

---
 mesonbuild/compilers/cuda.py | 31 +++++++++++++++++++------------
 1 file changed, 19 insertions(+), 12 deletions(-)

diff --git a/mesonbuild/compilers/cuda.py b/mesonbuild/compilers/cuda.py
index 3bde1cefa..0218dede8 100644
--- a/mesonbuild/compilers/cuda.py
+++ b/mesonbuild/compilers/cuda.py
@@ -290,8 +290,7 @@ class CudaCompiler(Compiler):
                 raise ValueError("-Xcompiler flag merging failed, unknown argument form!")
         return xflags
 
-    @classmethod
-    def _to_host_flags(cls, flags: T.List[str], phase: _Phase = _Phase.COMPILER) -> T.List[str]:
+    def _to_host_flags(self, flags: T.List[str], phase: _Phase = _Phase.COMPILER) -> T.List[str]:
         """
         Translate generic "GCC-speak" plus particular "NVCC-speak" flags to NVCC flags.
 
@@ -353,7 +352,7 @@ class CudaCompiler(Compiler):
             # an exception for -D (where this would be value-changing) and -U (because
             # it isn't possible to define a macro with a comma in the name).
 
-            if flag in cls._FLAG_PASSTHRU_NOARGS:
+            if flag in self._FLAG_PASSTHRU_NOARGS:
                 xflags.append(flag)
                 continue
 
@@ -384,19 +383,23 @@ class CudaCompiler(Compiler):
                 else:                            # -Isomething
                     val = flag[2:]
                 flag = flag[:2]                  # -I
-            elif flag in cls._FLAG_LONG2SHORT_WITHARGS or \
-                 flag in cls._FLAG_SHORT2LONG_WITHARGS:
+            elif flag in self._FLAG_LONG2SHORT_WITHARGS or \
+                 flag in self._FLAG_SHORT2LONG_WITHARGS:
                 # This is either -o or a multi-letter flag, and it is receiving its
                 # value isolated.
                 try:
                     val = next(flagit)           # -o something
                 except StopIteration:
                     pass
-            elif flag.split('=',1)[0] in cls._FLAG_LONG2SHORT_WITHARGS or \
-                 flag.split('=',1)[0] in cls._FLAG_SHORT2LONG_WITHARGS:
+            elif flag.split('=',1)[0] in self._FLAG_LONG2SHORT_WITHARGS or \
+                 flag.split('=',1)[0] in self._FLAG_SHORT2LONG_WITHARGS:
                 # This is either -o or a multi-letter flag, and it is receiving its
                 # value after an = sign.
                 flag, val = flag.split('=',1)    # -o=something
+            # Some dependencies (e.g., BoostDependency) add unspaced "-isystem/usr/include" arguments
+            elif flag.startswith('-isystem'):
+                val = flag[8:].strip()
+                flag = flag[:8]
             else:
                 # This is a flag, and it's foreign to NVCC.
                 #
@@ -418,7 +421,7 @@ class CudaCompiler(Compiler):
                     xflags.append('-prec-div=true')
                     xflags.append('-Xcompiler='+flag)
                 else:
-                    xflags.append('-Xcompiler='+cls._shield_nvcc_list_arg(flag))
+                    xflags.append('-Xcompiler='+self._shield_nvcc_list_arg(flag))
                     # The above should securely handle GCC's -Wl, -Wa, -Wp, arguments.
                 continue
 
@@ -427,7 +430,7 @@ class CudaCompiler(Compiler):
 
 
             # Take care of the various NVCC-supported flags that need special handling.
-            flag = cls._FLAG_LONG2SHORT_WITHARGS.get(flag,flag)
+            flag = self._FLAG_LONG2SHORT_WITHARGS.get(flag,flag)
 
             if   flag in {'-include','-isystem','-I','-L','-l'}:
                 # These flags are known to GCC, but list-valued in NVCC. They potentially
@@ -439,10 +442,14 @@ class CudaCompiler(Compiler):
                 # -U with comma arguments is impossible in GCC-speak (and thus unambiguous
                 #in NVCC-speak, albeit unportable).
                 if len(flag) == 2:
-                    xflags.append(flag+cls._shield_nvcc_list_arg(val))
+                    xflags.append(flag+self._shield_nvcc_list_arg(val))
+                elif flag == '-isystem' and val in self.host_compiler.get_default_include_dirs():
+                    # like GnuLikeCompiler, we have to filter out include directories specified
+                    # with -isystem that overlap with the host compiler's search path
+                    pass
                 else:
                     xflags.append(flag)
-                    xflags.append(cls._shield_nvcc_list_arg(val))
+                    xflags.append(self._shield_nvcc_list_arg(val))
             elif flag == '-O':
                 # Handle optimization levels GCC knows about that NVCC does not.
                 if   val == 'fast':
@@ -463,7 +470,7 @@ class CudaCompiler(Compiler):
                 xflags.append(flag)
                 xflags.append(val)
 
-        return cls._merge_flags(xflags)
+        return self._merge_flags(xflags)
 
     def needs_static_linker(self) -> bool:
         return False