[dpdk-dev] [RFC PATCH 7/9] eal/windows: fix rte_page_sizes with Clang on Windows

[Dmitry Kozlyuk]

Clang on Windows follows MS ABI where enum values are signed 32-bit,
Enum rte_page_size has members valued beyond 2^32.  EAL cannot use
-fno-ms-compatibility because its code is OS-dependent.  The only option
is to define these values outside enum, but this prohibits using
-fstrict-enums.  Another consequence is that enum rte_page_size cannot
be used to hold page size, because on Windows it won't be able to hold
all possible values.

Signed-off-by: Dmitry Kozlyuk <dmitry.kozliuk at gmail.com>
---
 lib/librte_eal/common/include/rte_memory.h | 6 ++++++
 lib/librte_eal/meson.build                 | 1 +
 2 files changed, 7 insertions(+)

diff --git a/lib/librte_eal/common/include/rte_memory.h b/lib/librte_eal/common/include/rte_memory.h
index 1742fde9a..5b0e2d8b5 100644
--- a/lib/librte_eal/common/include/rte_memory.h
+++ b/lib/librte_eal/common/include/rte_memory.h
@@ -34,8 +34,14 @@ enum rte_page_sizes {
 	RTE_PGSIZE_256M  = 1ULL << 28,
 	RTE_PGSIZE_512M  = 1ULL << 29,
 	RTE_PGSIZE_1G    = 1ULL << 30,
+/* Work around Clang on Windows being limited to 32-bit underlying type. */
+#if !defined(RTE_TOOLCHAIN_CLANG) || !defined(RTE_EXEC_ENV_WINDOWS)
 	RTE_PGSIZE_4G    = 1ULL << 32,
 	RTE_PGSIZE_16G   = 1ULL << 34,
+#else
+#define RTE_PGSIZE_4G  (1ULL << 32)
+#define RTE_PGSIZE_16G (1ULL << 34)
+#endif
 };
 
 #define SOCKET_ID_ANY -1                    /**< Any NUMA socket. */
diff --git a/lib/librte_eal/meson.build b/lib/librte_eal/meson.build
index 1730d603f..ec80bd6be 100644
--- a/lib/librte_eal/meson.build
+++ b/lib/librte_eal/meson.build
@@ -23,6 +23,7 @@ endif
 if cc.has_header('getopt.h')
 	cflags += ['-DHAVE_GETOPT_H', '-DHAVE_GETOPT', '-DHAVE_GETOPT_LONG']
 endif
+cflags += '-fno-strict-enums'
 sources = common_sources + env_sources
 objs = common_objs + env_objs
 headers = common_headers + env_headers
-- 
2.25.1