Wrap C APIs with pragmas enforcing -Werror=strict-prototypes

Force `-Werror=strict-prototypes` so that C API tests fail to compile if
we add a non-prototype declaration.  This should help avoid regressions
like bddecba4b333f7772029b4937d2c34f9f2fda6ca was fixing.

https://reviews.llvm.org/D70285
rdar://problem/57203137

8 files changed, 24 insertions, 48 deletions

diff --git a/llvm/include/llvm-c/Transforms/AggressiveInstCombine.h b/llvm/include/llvm-c/Transforms/AggressiveInstCombine.h
index c0b0141c3da..db061a7ad1f 100644
--- a/llvm/include/llvm-c/Transforms/AggressiveInstCombine.h
+++ b/llvm/include/llvm-c/Transforms/AggressiveInstCombine.h
@@ -15,11 +15,10 @@
 #ifndef LLVM_C_TRANSFORMS_AGGRESSIVEINSTCOMBINE_H
 #define LLVM_C_TRANSFORMS_AGGRESSIVEINSTCOMBINE_H
 
+#include "llvm-c/ExternC.h"
 #include "llvm-c/Types.h"
 
-#ifdef __cplusplus
-extern "C" {
-#endif
+LLVM_C_EXTERN_C_BEGIN
 
 /**
  * @defgroup LLVMCTransformsAggressiveInstCombine Aggressive Instruction Combining transformations
@@ -35,9 +34,7 @@ void LLVMAddAggressiveInstCombinerPass(LLVMPassManagerRef PM);
  * @}
  */
 
-#ifdef __cplusplus
-}
-#endif /* defined(__cplusplus) */
+LLVM_C_EXTERN_C_END
 
 #endif
 
diff --git a/llvm/include/llvm-c/Transforms/Coroutines.h b/llvm/include/llvm-c/Transforms/Coroutines.h
index 227e7cf0a36..687f9b55053 100644
--- a/llvm/include/llvm-c/Transforms/Coroutines.h
+++ b/llvm/include/llvm-c/Transforms/Coroutines.h
@@ -19,11 +19,10 @@
 #ifndef LLVM_C_TRANSFORMS_COROUTINES_H
 #define LLVM_C_TRANSFORMS_COROUTINES_H
 
+#include "llvm-c/ExternC.h"
 #include "llvm-c/Types.h"
 
-#ifdef __cplusplus
-extern "C" {
-#endif
+LLVM_C_EXTERN_C_BEGIN
 
 /**
  * @defgroup LLVMCTransformsCoroutines Coroutine transformations
@@ -48,8 +47,6 @@ void LLVMAddCoroCleanupPass(LLVMPassManagerRef PM);
  * @}
  */
 
-#ifdef __cplusplus
-}
-#endif /* defined(__cplusplus) */
+LLVM_C_EXTERN_C_END
 
 #endif
diff --git a/llvm/include/llvm-c/Transforms/IPO.h b/llvm/include/llvm-c/Transforms/IPO.h
index 51d00758128..cde3d246092 100644
--- a/llvm/include/llvm-c/Transforms/IPO.h
+++ b/llvm/include/llvm-c/Transforms/IPO.h
@@ -15,11 +15,10 @@
 #ifndef LLVM_C_TRANSFORMS_IPO_H
 #define LLVM_C_TRANSFORMS_IPO_H
 
+#include "llvm-c/ExternC.h"
 #include "llvm-c/Types.h"
 
-#ifdef __cplusplus
-extern "C" {
-#endif
+LLVM_C_EXTERN_C_BEGIN
 
 /**
  * @defgroup LLVMCTransformsIPO Interprocedural transformations
@@ -95,8 +94,6 @@ void LLVMAddStripSymbolsPass(LLVMPassManagerRef PM);
  * @}
  */
 
-#ifdef __cplusplus
-}
-#endif /* defined(__cplusplus) */
+LLVM_C_EXTERN_C_END
 
 #endif
diff --git a/llvm/include/llvm-c/Transforms/InstCombine.h b/llvm/include/llvm-c/Transforms/InstCombine.h
index 166f278d9a6..ebe17d66706 100644
--- a/llvm/include/llvm-c/Transforms/InstCombine.h
+++ b/llvm/include/llvm-c/Transforms/InstCombine.h
@@ -15,11 +15,10 @@
 #ifndef LLVM_C_TRANSFORMS_INSTCOMBINE_H
 #define LLVM_C_TRANSFORMS_INSTCOMBINE_H
 
+#include "llvm-c/ExternC.h"
 #include "llvm-c/Types.h"
 
-#ifdef __cplusplus
-extern "C" {
-#endif
+LLVM_C_EXTERN_C_BEGIN
 
 /**
  * @defgroup LLVMCTransformsInstCombine Instruction Combining transformations
@@ -35,9 +34,7 @@ void LLVMAddInstructionCombiningPass(LLVMPassManagerRef PM);
  * @}
  */
 
-#ifdef __cplusplus
-}
-#endif /* defined(__cplusplus) */
+LLVM_C_EXTERN_C_END
 
 #endif
 
diff --git a/llvm/include/llvm-c/Transforms/PassManagerBuilder.h b/llvm/include/llvm-c/Transforms/PassManagerBuilder.h
index d164c00d49c..6e13e18e063 100644
--- a/llvm/include/llvm-c/Transforms/PassManagerBuilder.h
+++ b/llvm/include/llvm-c/Transforms/PassManagerBuilder.h
@@ -14,13 +14,12 @@
 #ifndef LLVM_C_TRANSFORMS_PASSMANAGERBUILDER_H
 #define LLVM_C_TRANSFORMS_PASSMANAGERBUILDER_H
 
+#include "llvm-c/ExternC.h"
 #include "llvm-c/Types.h"
 
 typedef struct LLVMOpaquePassManagerBuilder *LLVMPassManagerBuilderRef;
 
-#ifdef __cplusplus
-extern "C" {
-#endif
+LLVM_C_EXTERN_C_BEGIN
 
 /**
  * @defgroup LLVMCTransformsPassManagerBuilder Pass manager builder
@@ -83,8 +82,6 @@ void LLVMPassManagerBuilderPopulateLTOPassManager(LLVMPassManagerBuilderRef PMB,
  * @}
  */
 
-#ifdef __cplusplus
-}
-#endif
+LLVM_C_EXTERN_C_END
 
 #endif
diff --git a/llvm/include/llvm-c/Transforms/Scalar.h b/llvm/include/llvm-c/Transforms/Scalar.h
index 6f3a3d8b375..93d79a20519 100644
--- a/llvm/include/llvm-c/Transforms/Scalar.h
+++ b/llvm/include/llvm-c/Transforms/Scalar.h
@@ -19,11 +19,10 @@
 #ifndef LLVM_C_TRANSFORMS_SCALAR_H
 #define LLVM_C_TRANSFORMS_SCALAR_H
 
+#include "llvm-c/ExternC.h"
 #include "llvm-c/Types.h"
 
-#ifdef __cplusplus
-extern "C" {
-#endif
+LLVM_C_EXTERN_C_BEGIN
 
 /**
  * @defgroup LLVMCTransformsScalar Scalar transformations
@@ -166,8 +165,6 @@ void LLVMAddUnifyFunctionExitNodesPass(LLVMPassManagerRef PM);
  * @}
  */
 
-#ifdef __cplusplus
-}
-#endif /* defined(__cplusplus) */
+LLVM_C_EXTERN_C_END
 
 #endif
diff --git a/llvm/include/llvm-c/Transforms/Utils.h b/llvm/include/llvm-c/Transforms/Utils.h
index 63594abfa46..30d1ae63de1 100644
--- a/llvm/include/llvm-c/Transforms/Utils.h
+++ b/llvm/include/llvm-c/Transforms/Utils.h
@@ -19,11 +19,10 @@
 #ifndef LLVM_C_TRANSFORMS_UTILS_H
 #define LLVM_C_TRANSFORMS_UTILS_H
 
+#include "llvm-c/ExternC.h"
 #include "llvm-c/Types.h"
 
-#ifdef __cplusplus
-extern "C" {
-#endif
+LLVM_C_EXTERN_C_BEGIN
 
 /**
  * @defgroup LLVMCTransformsUtils Transformation Utilities
@@ -45,9 +44,7 @@ void LLVMAddAddDiscriminatorsPass(LLVMPassManagerRef PM);
  * @}
  */
 
-#ifdef __cplusplus
-}
-#endif /* defined(__cplusplus) */
+LLVM_C_EXTERN_C_END
 
 #endif
 
diff --git a/llvm/include/llvm-c/Transforms/Vectorize.h b/llvm/include/llvm-c/Transforms/Vectorize.h
index e383481fe4f..0de45838139 100644
--- a/llvm/include/llvm-c/Transforms/Vectorize.h
+++ b/llvm/include/llvm-c/Transforms/Vectorize.h
@@ -20,11 +20,10 @@
 #ifndef LLVM_C_TRANSFORMS_VECTORIZE_H
 #define LLVM_C_TRANSFORMS_VECTORIZE_H
 
+#include "llvm-c/ExternC.h"
 #include "llvm-c/Types.h"
 
-#ifdef __cplusplus
-extern "C" {
-#endif
+LLVM_C_EXTERN_C_BEGIN
 
 /**
  * @defgroup LLVMCTransformsVectorize Vectorization transformations
@@ -43,8 +42,6 @@ void LLVMAddSLPVectorizePass(LLVMPassManagerRef PM);
  * @}
  */
 
-#ifdef __cplusplus
-}
-#endif /* defined(__cplusplus) */
+LLVM_C_EXTERN_C_END
 
 #endif