cmake detects clang-cl as clang

Question

I built boringssl with cmake and msvc Then I tried to build with clang-cl so I used -T"LLVM-vs2014" in vmake arguments

Clang-cl uses cl arguments however cmake used gcc style arguments without adding -Xclang

arrowd · Accepted Answer · 2023-06-06T19:52:22.737

5

The proper way to handle this case is checking for

(CMAKE_CXX_COMPILER_ID STREQUAL Clang AND "x${CMAKE_CXX_SIMULATE_ID}" STREQUAL "xMSVC"))

edited Jun 06 '23 at 19:52

answered Jun 15 '18 at 10:12

arrowd

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Why the x is necessary before ${CMAKE_CXX_SIMULATE_ID}? – János Benjamin Antal Mar 20 '20 at 00:05
He is using `"x${CMAKE_CXX_SIMULATE_ID}"`. So if `${CMAKE_CXX_SIMULATE_ID} == MSVC` you need to add `x`. – Royi May 03 '20 at 13:55
Is there any reason to put the x in both instead of doing `"${CMAKE_CXX_SIMULATE_ID}" STREQUAL "MSVC"`? – IDontKnowWhatToPutAsMyUsername Jun 06 '23 at 19:12
IIRC, the "x" is used near "MSVC" because MSVC itself is a CMake variable and the `if` command may dereference it. – arrowd Jun 06 '23 at 19:59

score 0 · Answer 2 · answered Jun 14 '18 at 17:51

0

the problem was here :

if(CMAKE_COMPILER_IS_GNUCXX OR "${CMAKE_CXX_COMPILER_ID}" STREQUAL "Clang")
  set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wall -Wshadow -Werror -Wno-error=shadow -Wno-error=unused-value -ggdb -std=gnu89")
  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wall -Wshadow -Werror -Wno-error=shadow -Wno-error=unused-value -ggdb -std=c++0x")

I changed Clang to Clng so clang-cl wasn't identified as clang.exe which take gcc style arguments

answered Jun 14 '18 at 17:51

dev65

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Can you clarify why you chose the string `Clng`? Is that an identifier for a specific version of clang, or is it meant as a random string that matches nothing? – emmenlau Sep 03 '20 at 08:30

cmake detects clang-cl as clang

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