[Buildroot] [PATCH 1/1] toolchain-external wrapper: don't pass march/mcpu if mtune is on cmdline

[Thomas De Schampheleire <patrickdepinguin@gmail.com>]

From: Thomas De Schampheleire <thomas.de.schampheleire@gmail.com>

Before commit 5715d2dcf48a39c16a3f3e41c97109613fed121d, the external
toolchain wrapper would not pass its own march/mcpu/mtune flags to the real
compiler if at least one of them was passed on the wrapper command-line.

The mentioned commit intended to remove the passing of an mtune parameter
coming from Buildroot, which was always empty after some other refactoring,
but the changes have the side-effect that march/mcpu is now also passed when
mtune is already given on the command-line. In that case, only mtune should
be passed to the real compiler.

Restore part of the original toolchain wrapper code to check the presence of
mtune on the command-line.

Signed-off-by: Thomas De Schampheleire <thomas.de.schampheleire@gmail.com>
---
 toolchain/toolchain-external/ext-toolchain-wrapper.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/toolchain/toolchain-external/ext-toolchain-wrapper.c b/toolchain/toolchain-external/ext-toolchain-wrapper.c
index e2d01dc..f84b840 100644
--- a/toolchain/toolchain-external/ext-toolchain-wrapper.c
+++ b/toolchain/toolchain-external/ext-toolchain-wrapper.c
@@ -35,9 +35,10 @@ static char sysroot[PATH_MAX];
  * Currently, we have:
  * 	-mfloat-abi=
  * 	-march=
+ * 	-mtune=
  * 	-mcpu=
  */
-#define EXCLUSIVE_ARGS	3
+#define EXCLUSIVE_ARGS	4
 
 static char *predef_args[] = {
 	path,
@@ -177,11 +178,12 @@ int main(int argc, char **argv)
 
 #if defined(BR_ARCH) || \
     defined(BR_CPU)
-	/* Add our -march/cpu/abi flags, but only if none are
-	 * already specified on the commandline
+	/* Add our -march/cpu flags, but only if none of
+	 * -march/mtune/mcpu are already specified on the commandline
 	 */
 	for (i = 1; i < argc; i++) {
 		if (!strncmp(argv[i], "-march=", strlen("-march=")) ||
+		    !strncmp(argv[i], "-mtune=", strlen("-mtune=")) ||
 		    !strncmp(argv[i], "-mcpu=",  strlen("-mcpu=" )))
 			break;
 	}
-- 
1.8.5.1